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OBJECTIVES: To assess the cost-effectiveness (CE) of transcatheter aortic valve implantation (TAVI) in Italy, considering patient groups with different surgical risk. METHODS: A Markov model with a 1-month cycle length, comprising eight different health states, defined by the New York Heart Association functional classes (NYHA I-IV), with and without stroke plus death, was used to estimate the CE of TAVI for intermediate-, high-risk and inoperable patients considering surgical aortic valve replacement or medical treatment as comparators according to the patient group. The Italian National Health System perspective and 15-year time horizon were considered. In the base-case analysis, effectiveness data were retrieved from published efficacy data and total direct costs (euros) were estimated from national tariffs. A scenario analysis considering a micro-costing approach to estimate procedural costs was also considered. The incremental cost-effectiveness ratio (ICER) was expressed both in terms of costs per life years gained (LYG) and costs per quality adjusted life years (QALY). All outcomes and costs were discounted at 3% per annum. Univariate and probabilistic sensitivity analyses (PSA) were performed to assess robustness of results. RESULTS: Over a 15-year time horizon, the higher acquisition costs for TAVI were partially offset in all risk groups because of its effectiveness and safety profile. ICERs were 8338/QALY, 11,209/QALY and 10,133/QALY, respectively, for intermediate-, high-risk and inoperable patients. ICER values were slightly higher in the scenario analysis. PSA suggested consistency of results. CONCLUSIONS: TAVI would be considered cost-effective at frequently cited willingness-to-pay thresholds; further studies could clarify the CE of TAVI in real-life scenarios.
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Estenosis de la Válvula Aórtica , Implantación de Prótesis de Válvulas Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Estenosis de la Válvula Aórtica/cirugía , Análisis Costo-Beneficio , Humanos , Italia , Años de Vida Ajustados por Calidad de Vida , Resultado del TratamientoRESUMEN
Data on this paper describe the monitoring of different size ranges of particulate matter on dwellings positioned close to an integral cycle steel plant. Data were collected by eight channel (PM0.3, PM0.5, PM0.7, PM1, PM2, PM3, PM5, PM10) optical particle counters positioned in two sites. The data were recorded as counts-per-minute for every size channel in a three months survey from June to September 2015. Basic statistical elaboration and boxplot graphs as well as raw data are included. The data are related to "Characterization of variability of air particulate matter size profiles recorded by Optical Particle Counters near a complex emissive source by use of Self-Organizing Map algorithm" Licen et al.,2019, in which a statistical elaboration by Self-Organizing Map algorithm is proposed.
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Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by hyperplastic megakaryopoiesis and myelofibrosis. We recently described the upregulation of MAF (v-maf avian musculoaponeurotic fibrosarcoma oncogene homolog) in PMF CD34+ hematopoietic progenitor cells (HPCs) compared to healthy donor. Here we demonstrated that MAF is also upregulated in PMF compared with the essential thrombocytemia (ET) and polycytemia vera (PV) HPCs. MAF overexpression and knockdown experiments shed some light into the role of MAF in PMF pathogenesis, by demonstrating that MAF favors the megakaryocyte and monocyte/macrophage commitment of HPCs and leads to the increased expression of proinflammatory and profibrotic mediators. Among them, we focused our further studies on SPP1 and LGALS3. We assessed SPP1 and LGALS3 protein levels in 115 PMF, 47 ET and 24 PV patients plasma samples and we found that SPP1 plasma levels are significantly higher in PMF compared with ET and PV patients. Furthermore, in vitro assays demonstrated that SPP1 promotes fibroblasts and mesenchymal stromal cells proliferation and collagen production. Strikingly, clinical correlation analyses uncovered that higher SPP1 plasma levels in PMF patients correlate with a more severe fibrosis degree and a shorter overall survival. Collectively our data unveil that MAF overexpression contributes to PMF pathogenesis by driving the deranged production of the profibrotic mediator SPP1.
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Médula Ósea/metabolismo , Médula Ósea/patología , Fibrosis/metabolismo , Fibrosis/patología , Osteopontina/metabolismo , Proteínas Proto-Oncogénicas c-maf/metabolismo , Antígenos CD34/metabolismo , Proliferación Celular/fisiología , Células Madre Hematopoyéticas/metabolismo , Células Madre Hematopoyéticas/patología , Humanos , Megacariocitos/metabolismo , Megacariocitos/patología , Trastornos Mieloproliferativos/metabolismo , Trastornos Mieloproliferativos/patología , Policitemia Vera/metabolismo , Policitemia Vera/patología , Mielofibrosis Primaria/metabolismo , Mielofibrosis Primaria/patología , Trombocitemia Esencial/metabolismo , Trombocitemia Esencial/patologíaRESUMEN
Gait and balance disorders are often major causes of handicap in patients with cerebellar ataxia. Although it was thought that postural and balance disorders in cerebellar ataxia were not treatable, recent studies have demonstrated the beneficial effects of rehabilitation programs. This article is the first systematic review on the treatment of postural disorders in cerebellar ataxia. Nineteen articles were selected, of which three were randomized, controlled trials. Various aetiologies of cerebellar ataxia were studied: five studies assessed patients with multiple sclerosis, four assessed patients with degenerative ataxia, two assessed stroke patients and eight assessed patients with various aetiologies. Accurate assessment of postural disorders in cerebellar ataxia is very important in both clinical trials and clinical practice. The Scale for the Assessment and Rating of Ataxia (SARA) is a simple, validated measurement tool, for which 18 of the 40 points are related to postural disorders. This scale is useful for monitoring ataxic patients with postural disorders. There is now moderate level evidence that rehabilitation is efficient to improve postural capacities of patients with cerebellar ataxia - particularly in patients with degenerative ataxia or multiple sclerosis. Intensive rehabilitation programs with balance and coordination exercises are necessary. Although techniques such as virtual reality, biofeedback, treadmill exercises with supported bodyweight and torso weighting appear to be of value, their specific efficacy has to be further investigated. Drugs have only been studied in degenerative ataxia, and the level of evidence is low. There is now a need for large, randomized, controlled trials testing rehabilitation programs suited to postural and gait disorders of patients with cerebellar ataxia.
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Ataxia Cerebelosa/rehabilitación , Terapia por Ejercicio , Equilibrio Postural , Trastornos de la Sensación/rehabilitación , Ataxia Cerebelosa/complicaciones , Humanos , Trastornos de la Sensación/etiologíaRESUMEN
About 80 papers dealing with verticality after stroke have been published in the last 20years. Here we reviewed the reasons and findings that explain why measuring verticality perception after stroke is interesting. Research on verticality perception after stroke has contributed to improve the knowledge on brain mechanisms, which build up and update a sense of verticality. Preliminary research using modern techniques of brain imaging has shown that the posterior lateral thalamus and the parietal insular cortex are areas of interest for this internal model of verticality. How they interact and are critical remains to be investigated. From a clinical standpoint, it has now been clearly established that biases in verticality perception are frequent after a stroke, causing postural disorders. Measuring the postural vertical with the wheel paradigm has allowed elucidating the mechanisms of lateropulsion, leading or not to a pushing. Schematically, patients with a hemispheric stroke align their erect posture with an erroneous reference of verticality, tilted to the side opposite the lesion. In patients with a brainstem stroke lateropulsion is usually ipsilesional, and results rather from a pathological asymmetry of tone, through vestibulo-spinal mechanisms. These evolutions of concepts and measurement standards of verticality representation should guide the emergence of rehabilitation programs specifically dedicated to the sense of verticality after stroke. Indeed, several pilot studies using appropriate somatosensory stimulation suggest the possibility to recalibrate the internal model of verticality biased by the stroke, and to improve uprightness. Vestibular stimulations seem to be less relevant and efficient.
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Equilibrio Postural , Percepción Espacial , Accidente Cerebrovascular/psicología , Humanos , Percepción VisualRESUMEN
Higher plants play a key role in Bioregenerative Life-Support Systems (BLSS) for long-term missions in space, by regenerating air through photosynthetic CO2 absorption and O2 emission, recovering water through transpiration and recycling waste products through mineral nutrition. In addition, plants could provide fresh food to integrate into the crew diet and help to preserve astronauts' wellbeing. The ESA programme Micro-Ecological Life-Support System Alternative (MELiSSA) aims to conceive an artificial bioregenerative ecosystem for resources regeneration, based on both microorganisms and higher plants. Soybean [Glycine max (L.) Merr.] is one of the four candidate species studied for soilless (hydroponic) cultivation in MELiSSA, because of the high nutritional value of the seeds. Within the MELiSSA programme - Food characterisation Phase I, the aim of the research carried out on soybean at the University of Naples was to select the most suitable European cultivars for cultivation in BLSS. In this context, a concise review on the state-of-the-art of soybean cultivation in space-oriented experiments and a summary of research activity for the preliminary theoretical selection and subsequent agronomical evaluation of four cultivars will be presented in this paper.
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Alimentos , Glycine max/crecimiento & desarrollo , Sistemas de Manutención de la Vida , Regeneración/fisiología , Suelo , Productos Agrícolas/crecimiento & desarrolloRESUMEN
OBJECTIVE: An Achilles tendon (AT) vibration is known to disrupt the postural control in standing ("vibration-induced falling", VIF) and to backward tilt the postural vertical in restrained sitting position, suggesting a link between AT vibration and internal representations involved in postural control. A recalibration of some troubles in body orientation by oriented sensory manipulations could be of great clinical interest. In order to use the VIF paradigm in a procedure suitable for a rehabilitation context, AT vibration deserves to be more investigated in sitting, for security reasons, and first in young participants. METHOD: In 12 healthy participants (6 men/6 women; 23.3±1.9 years), posturographic data to AT vibrations (85 Hz) were recorded over 30 s standing and 40 s sitting trials. RESULTS: Surprisingly, four types of differences were found between standing and sitting AT vibrations: presence/absence of VIF and kinesthetic illusion, opposite directions of the centre of foot pressure (CoP) displacements, different temporal profiles. In standing: VIF without kinesthetic illusion, rapid backward shift of CoP with a peak of -54.6±11.3 mm (with respect to baseline P<0.001) 2.8±0.2 s after vibration onset. In sitting: surprising systematic forward shift of the CoP throughout the duration of AT vibration with a maximum of 27.9±18.9 mm (P<0.05 with respect to the baseline) 19.6±0.3 s after vibration onset, associated with a kinesthetic illusion in most subjects. CONCLUSION: The present study invalidates our idea to extend in sitting the VIF paradigm but the unexpected results open a new window about the basic mechanisms underlying muscle vibration effects.
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Tendón Calcáneo/fisiología , Equilibrio Postural/fisiología , Presión , Femenino , Humanos , Masculino , Adulto JovenRESUMEN
In recent years, formulations of the Italian cold cut mortadella have changed to meet evolving tastes and nutritional trends. The aim of the present study was to analyze the physical, chemical, and sensory characteristics of currently produced mortadella. Representative samples of Italian mortadella (13 brands, 3 samples/brand) were analyzed. Three groups of products were identified according to their chemical compositions. The median cluster was composed of 54.80% moisture, 26.19% fat, and 15.02% protein, whereas the other two clusters were characterized by a higher percentage of moisture or fat. These results indicate that, on average, the current products are characterized by less fat (-5%) and salt (-10%) content compared to products 20 years ago.
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Fenómenos Químicos , Productos de la Carne/análisis , Percepción del Gusto/fisiología , Gusto/fisiología , Animales , Manipulación de Alimentos/métodos , Humanos , Cloruro de Sodio Dietético/análisis , PorcinosRESUMEN
The evaluation of the efficiency with which the reactions involving nitrite proceed in mortadella and of the effect exercised on their kinetics by some variables (ingoing amount of sodium nitrite and temperature) is the purpose of this work. Kinetics parameters were calculated at each level of nitrite added (40, 70, 100 and 150 mg/kg) and at five temperature (55°, 60°, 65°, 70° and 72 °C). While the colour formation reaction is favoured by low activation energy, it becomes crucial to enable nitrite to proceed according to direct reduction thus preventing an increase in nitrate concentration as well as an excess of nitric oxide in the product. Kinetics data suggest that this scope is performed when the product achieves the temperature of 65 °C as fast as possible with an ingoing amount of sodium nitrite of 70 mg/kg.
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Manipulación de Alimentos/métodos , Productos de la Carne/análisis , Nitrito de Sodio/análisis , Nitrito de Sodio/metabolismo , Animales , Color , Cinética , Óxido Nítrico/análisis , Óxido Nítrico/metabolismo , Porcinos , TemperaturaRESUMEN
The time required to complete a fast and accurate movement is a function of its amplitude and the target size. This phenomenon refers to the well known speed-accuracy trade-off. Some interpretations have suggested that the speed-accuracy trade-off is already integrated into the movement planning phase. More specifically, pointing movements may be planned to minimize the variance of the final hand position. However, goal-directed movements can be altered at any time, if for instance, the target location is changed during execution. Thus, one possible limitation of these interpretations may be that they underestimate feedback processes. To further investigate this hypothesis we designed an experiment in which the speed-accuracy trade-off was unexpectedly varied at the hand movement onset by modifying separately the target distance or size, or by modifying both of them simultaneously. These pointing movements were executed from an upright standing position. Our main results showed that the movement time increased when there was a change to the size or location of the target. In addition, the terminal variability of finger position did not change. In other words, it showed that the movement velocity is modulated according to the target size and distance during motor programming or during the final approach, independently of the final variability of the hand position. It suggests that when the speed-accuracy trade-off is unexpectedly modified, terminal feedbacks based on intermediate representations of the endpoint velocity are used to monitor and control the hand displacement. There is clearly no obvious perception-action coupling in this case but rather intermediate processing that may be involved.
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Función Ejecutiva/fisiología , Retroalimentación Sensorial/fisiología , Percepción de Movimiento/fisiología , Movimiento/fisiología , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Adulto , Mano/fisiología , Humanos , Masculino , Orientación/fisiología , Adulto JovenAsunto(s)
Hemorragia Subaracnoidea , Adulto , Muerte Encefálica , Resultado Fatal , Humanos , Hipoxia-Isquemia Encefálica/diagnóstico , Hipoxia-Isquemia Encefálica/diagnóstico por imagen , Masculino , Radiografía , Hemorragia Subaracnoidea/diagnóstico , Hemorragia Subaracnoidea/diagnóstico por imagenRESUMEN
La Ventilación Mecánica Prolongada (VMP) ha sido definida como aquella mayor de 21 días por al menos 6 horas diarias. Este fenómeno es un creciente problema para las Unidades de Cuidados Intensivos (UCI) en todo el mundo. Los consensos internacionales señalan que los pacientes con VMP deben ser tratados en unidades diferentes a las UCI, con protocolos especializados multiprofesionales dedicados a intentar el retiro del respirador. En nuestro Centro hemos recibido desde el año 2002 a 31 pacientes con VMP y les hemos aplicado un Protocolo de Rehabilitación Respiratoria Integral para ese objetivo. Las patologías predominantes fueron neuromusculares. El protocolo tiene 4 etapas progresivas, las 2 primeras comprenden la evaluación general y el inicio de terapias multiprofesionales. Las 2 siguientes consisten en retiro progresivo del respirador y continuación de terapias. Se midió la presión inspiratoria, presión espiratoria espiratoria máximas (PImáx y PEmáx) y la presión inspiratoria máxima sostenida (PIms), también se evaluó la actividad muscular de cuello, tronco y extremidades, así como el estado general y nutritivo, el nivel de conciencia y la calidad del apoyo familiar. Se entra a etapa 3 cuando los valores de PImáx y PEmáx son 60 y 50 cmH2O, respectivamente. Fueron excluidos de llegar a las últimas 2 etapas 7 pacientes, quienes no lograron este nivel de presiones. Resultados: 19pacientes (61 por ciento) con promedio de edad de 44 años (16-77), fueron retirados del respirador, 5 están aún en etapas 2 y 3; el promedio de VMP fue de 238 días y de 74 días a contar desde el ingreso a etapa 3. El promedio de mejoría de PImax fue de 59 por ciento, la PEmáx 60 por ciento y la PIms 61 por ciento, todos valores con significación estadística (p <0,001). El control cefálico y de tronco mejoró con las terapias. También el daño cognitivo, la depresión y la alteración de la función deglutoria...
Prolonged mechanical ventilation (PMV) is defined as greater than 21 days of mechanical ventilation for at least 6hours per day and is an increasing problem for the Intensive Care Units in all over the world. Many expert consensus groups recommend that long-term facilities may be a useful resource of care to implement integrated and specialized protocols for weaning from PMV. Since 2002 our center admitted 31 patients in PMV who were included on an Integral Respiratory Rehabilitation Protocol that was applied for our primary outcome of weaning success. Neuromuscular diseases were the main cause requiring PMV. The protocol applied consists of 4 successive stages, the first two oriented to evaluation and initiation of multiprofessional therapies, the next two are dedicated to progressive weaning and continuation of therapy. Peak inspiratory and expiratory pressures, and maximal sustained inspiratory pressure (PImax, PEmax and PIms) were measured, additionally muscular activity from neck, trunk and legs, general and nutritional condition, conscience level and family support were evaluated. Entry to stage 3 was defined when the PImax and PEmax were 60 and 50 cmH2O. Seven patients who failed to achieve this pressure levels were excluded. Results: 19 patients (61 percent) with a mean age of 44 years (16-77) had successful weaning and 5 patients are still in stage 2 or 3. Mean duration of PMV was 238 days. Mean Time on Mechanical Ventilation from the beginning of stage3 until the final weaning was 74 days. PImax, PEmax and PIms increased in 59, 60 and 61 percent each, all with statistical significance p <0.001, cephalic and trunk muscle control was increased with integrated therapies. The cognitive impairment, depression and swallowing disorders were professionally treated. Conclusion: A specialized, multiprofessional integrated protocol for PMV in our center permitted a successful weaning rate comparable to the best international series.
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Humanos , Masculino , Adolescente , Adulto , Femenino , Persona de Mediana Edad , Protocolos Clínicos , Desconexión del Ventilador/métodos , Enfermedades Respiratorias/rehabilitación , Unidades de Cuidados Intensivos , Músculos Respiratorios/fisiopatología , Estudios Prospectivos , Respiración Artificial/métodos , Factores de TiempoRESUMEN
Protein composition was examined in order to find markers that could be useful in technology optimization. The behaviour of sarcoplasmic and myofibrillar proteins during the processing of roast pork was studied at the various processing steps, utilising some electrophoretic (SDS-PAGE, 2DE and IEF) and thermometric (DSC) techniques and evaluating the content of amino acids produced. The relevance of desmin as a marker of structural modification was emphasised. The extraction of myofibrillar proteins by brine, the formation of a protein network at 62°C and the evaluation of the exudate produced during cooking are the crucial steps that should be monitored when a new industrial process is to be optimised.
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The purpose of this study was to develop and validate a new tool to objectively quantify trunk orientation at the bedside, especially dedicated to the measurement of the lateropulsion in acute and subacute stroke patients. We developed software to analyze 2D movement with a CMOS camera (Logitech Quickcam Pro 4000) and to calculate the orientation of a segment defined by two color markers. First, the accuracy, reproducibility and noise when measuring segment orientations were evaluated with the CMOS camera placed in different positions, and second trunk orientation was measured in static and in dynamic conditions both with a CMOS camera and with a gold standard 3D video system (BTS SMART-e). Results showed that the measurement was accurate (mean error=0.05+/-0.12 degrees), reproducible (S.D. over five measurements=0.005 degrees ) and steady (noise signal=0.02 degrees ). The data obtained with the CMOS camera were highly correlated with those obtained with the 3D video system both in static and in dynamic conditions. However, the CMOS camera must be relatively well centered on the measured segment to avoid error due to image distortion. The parallax error was negligible. In conclusion, this could be an important step in the postural assessment of acute and subacute stroke patients. The CMOS camera, a simple, portable, compact, low-cost, commercially available apparatus is the first tool to objectively quantify lateropulsion at the bedside. This method could also support the development of a rehabilitation program for trunk orientation based on biofeedback using the real-time signal provided by the device.
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Procesamiento de Imagen Asistido por Computador/instrumentación , Postura/fisiología , Accidente Cerebrovascular/fisiopatología , Tórax/fisiología , Grabación de Cinta de Video/instrumentación , Algoritmos , Estudios de Factibilidad , Humanos , Reproducibilidad de los Resultados , Programas InformáticosRESUMEN
An analytical method based on the detection of specific DNA was developed and applied to mortadella samples with and without pistachio (Pistacia vera). The method is proposed for the detection of traces of pistachio deriving from previous processes or from accidental contamination, since in predisposed individuals pistachios can cause allergic reactions leading to anaphylactic shock. Three pairs of primers were identified and tested by polymerase chain reaction (PCR) on mortadella samples prepared with pistachio. Accidental contamination was also simulated. The optimized PCR was able to detect the presence of pistachio, even at low concentrations. The primers pair PSTC 1-2 is suggested for unambiguous identification of pistachio in mortadella. The limit of detection for this primers pair was 100 mg kg-1. No interference was observed from other spices or ingredients utilized in the formulation of the mortadella. The method enabled the identification of possible traces of pistachio remaining in the production plant after less than thorough washing.
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Alérgenos/análisis , Contaminación de Alimentos/análisis , Productos de la Carne/análisis , Pistacia/inmunología , Secuencia de Bases , ADN de Plantas/análisis , Análisis de los Alimentos/métodos , Manipulación de Alimentos , Datos de Secuencia Molecular , Pistacia/genética , Reacción en Cadena de la Polimerasa/métodosRESUMEN
For an efficient membrane bioreactor design, transport phenomena determining the overall mass flux of metabolites, catabolites, cell regulatory factors, and immune-related soluble factors, need to be clarified both experimentally and theoretically. In this work, experiments and calculations aimed at discerning the simultaneous influence of both diffusive and convective mechanisms to the transport of metabolites. In particular, the transmembrane mass flux of glucose, bovine serum albumin (BSA), APO-transferrin, immunoglobulin G, and ammonia was experimentally measured, under pressure and concentration gradients, through high-flux microporous hydrophilic poly-ether-sulphone (PES-HFMs) and poly-sulphone hollow fiber membranes (PS-HFMs). These data were analyzed by means of a model based on the mechanism of capillary pore diffusion, assuming that solute spherical molecules pass through an array of solvent-filled cylindrical pores with a diffusive permeation corrected for friction and steric hindrances. Additionally, resistances to the mass transfer were taken into account. Convective permeation data were discussed in terms of morphological properties of the polymeric membranes, molecular Stokes radius, and solute-membrane interactions according to information given by contact angle measurements. The observed steady-state hydraulic permeance of PS-HFMs was 0.972 L/m2hmbar, about 15.6-fold lower than that measured for PES-HFMs (15.2 L/m2h); in general, PS-HFMs provided a significant hindrance to the transport of target species. Diffusion coefficients of metabolites were found to be similar to the corresponding values in water through PES-HFMs, but significantly reduced through PS-HFMs (D(Glucose)(Membrane)=2.8x10(-6)+/-0.6x10(-6)cm2/s, D(BSA)(Membrane)=6.4 x 10(-7)+/-1 x 10(-7)cm(/s, D(Apotransferrin)(Membrane)=2.3 x 10(-7)+/-0.25 x 10(-7)cm2/s).
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Transporte Biológico , Hepatocitos/citología , Hepatocitos/metabolismo , Hígado/citología , Membranas Artificiales , Amoníaco/análisis , Animales , Apoenzimas/análisis , Fenómenos Biofísicos , Biofisica , Bovinos , Técnicas de Cultivo de Célula , Células Cultivadas , Difusión , Glucosa/análisis , Humanos , Inmunoglobulina G/análisis , Microscopía Electrónica de Rastreo , Polímeros/química , Porosidad , Albúmina Sérica Bovina/análisis , Sulfonas/química , Tromboplastina/análisisRESUMEN
O jurupoca, Hemisorubim platyrhynchos, é o sexto maior pimelodídeo do Pantanal. Sua idade e crescimento foram estudados a partir dos espinhos de nadadeiras peitorais de exemplares coletados no rio Cuiabá, Pantanal mato-grossense. Os exemplares provieram da pesca comercial e experimental com linha e anzol. A análise do índice de incremento marginal não permitiu que se distinguissem a periodicidade e a época de formação dos anéis de crescimento (H = 4,142; p = 0,247). Porém, o declínio acentuado do índice de incremento marginal registrado na vazante sugere que esse seja o período de formação dos anéis. A estimativa dos parâmetros que descrevem a curva de crescimento de von Bertalanffy, ajustada por meio de regressão não-linear aos comprimentos observados e com o valor do LØ fixado em 64,0 cm (comprimento furcal), foi de k = 0,222 ano-1 e to = -2,149 anos. A longevidade dos indivíduos foi estimada em 11,4 anos. Os resultados indicam que o comprimento furcal é bom preditor da idade para os indivíduos dessa espécie de peixe.
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Animales , Bagres , Longevidad , Brasil , Agua DulceRESUMEN
The Duckbill Catfish, Sorubim lima, is a predator of large South American rivers. The age and growth of S. lima were studied based on the pectoral fin-spines of samples collected from the Cuiabá River, Pantanal. The samples were taken from commercial and experimental hook-and-line fishing. An analysis of the marginal increment suggests that the growth rings are formed once a year during the dry season, from July to September (ANOVA type I: F = 4.183; g.l. = 3 and 104; p = 0.008). The estimate of the parameters that describe von Bertalanffy's growth curve by nonlinear regression of the observed lengths in the age were: L infinity = 56.0 cm (fork length); k = 0.245 year-1; to = -2.605 years. The animals were estimated to have a life span of 9.6 years. The findings indicate that the fork length is a good predictor of the age of individuals of this fish species.