RESUMEN
OBJECTIVES: Advanced practice nursing roles in cancer care are diverse and exist across the cancer care continuum. However, the titles used and the scope of practice differ across countries. This diversity is likely to be misleading to patients and influence nurses' contribution to health care. An understanding of the current state of advanced practice nursing roles in cancer care internationally is needed to inform opportunities for future role development and enhance cancer nursing career pathways. METHODS: This scoping review included a systematic search of four databases: MEDLINE, CINAHL, PsycINFO, and Academic Search Complete. Independent screening for papers meeting the review's inclusion criteria was undertaken using online screening software. Data extraction, coding, and mapping were undertaken in NVivo 12. RESULTS: Of the 13,409 records identified, 108 met the review's inclusion criteria. A variety of roles in cancer care settings were described. The United States and the United Kingdom had the most titles for advanced practice nursing roles. Tumor-specific roles were described and integrated into different phases of the cancer care continuum. Trends in continuing professional development for advanced practice nurses in cancer care included the rise in Fellowship programs in the United States and practice-based education in the United Kingdom. CONCLUSIONS: The differences in advanced practice nursing roles in cancer care allow regional and institutional variation to meet the needs of patient populations and health care system demands. However, a lack of clarity surrounding titles and roles results in confusion and underutilization of these nurses' highly specialized skill sets. IMPLICATIONS FOR NURSING PRACTICE: Incongruence in titles and scope of practice internationally will ultimately result in a merging of roles. There is a need for international agreement on education requirements for advanced practice nursing roles to promote career pathways.
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Enfermería de Práctica Avanzada , Neoplasias , Rol de la Enfermera , Enfermería Oncológica , Humanos , Neoplasias/enfermería , Estados Unidos , Reino UnidoRESUMEN
In this chapter, a protocol to design affinity chromatography matrices with short peptide ligands immobilized for protein purification is described. The first step consists of the synthesis of a combinatorial peptide library on the hydroxymethylbenzoyl (HMBA)-ChemMatrix resin by the divide-couple-recombine (DCR) method using the Fmoc chemistry. Next, the library is screened with the protein of interest labeled with a fluorescent dye or biotin. Subsequently, peptides contained on positive beads are identified by tandem matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS/MS), and those sequences showing greater consensus are synthesized in larger quantities and immobilized on chromatographic supports. Finally, target protein adsorption on peptide affinity matrices is evaluated through equilibrium adsorption isotherms and breakthrough curves.
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Cromatografía de Afinidad , Técnicas Químicas Combinatorias , Biblioteca de Péptidos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
Fukui functions (FFs) are chemical descriptors that are useful to explain the reactivity of systems toward electron transfer. Whereas they have been widely employed for molecules, their application to extended systems is scarce. One of the reasons for the limited development of such analysis in solids is the improper evaluation of FFs in the usual computational approaches based on density functional theory and periodic boundary conditions. In this work we compare the available approaches and propose a new method based on the interpolation of partially charged systems that mitigates some of the problems encountered. We discuss the reactivity of alkaline earth oxides (MgO, CaO, SrO, and BaO) in terms of the FF analysis, providing a robust way to account for the higher reactivity of surface oxygen sites compared with bulk sites.
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The aim of the study was to evaluate the effects of a cashew nut shell oil and commercial castor oil blend (CNSL-Castor oil) on the performance and microbiota of broiler chickens with and without coccidiosis challenge. A total of 864 one-day-old male chicks (Cobb) were randomly distributed to receive 6 treatments (8 pens/treatment; 18 chicks/pen) in a 3 × 2 factorial, with 3 additives (control [non-additives], 100 ppm sodium monensin, or 0.15% CNSL-Castor oil blend), and 2 levels of coccidiosis challenge at 14 D of age (unchallenged or inoculated by gavage with 1 mL of solution containing oocysts sporulated with Eimeria tenella, Eimeria acervulina, and Eimeria maxima). No differences in productive performance were observed among treatments in the pre-challenge period and in unchallenged birds (P > 0.05). Seven-days post-challenge, birds receiving monensin performed better than birds in the positive control group (non-additive and challenge) or in the CNSL-Castor oil group (P > 0.05). However, 14 D post-challenge, birds supplemented with CNSL-Castor oil presented higher weight gain and better feed conversion (P > 0.05), without any change in feed intake (P > 0.05). During the accumulated period (1 to 42 D of age), the live weight, weight gain, and feed intake did not differ between the CNSL-Castor oil and monensin groups, both of which presented higher values than the positive control. Lactobacillus spp. and Clostridium perfringens numbers were increased in the challenged birds (P < 0.05). CNSL-Castor oil supplementation reduced Clostridium cluster XIV, C. perfringens, and S. aureus, compared with the monensin and control groups (P > 0.05). In addition, the CNSL-Castor oil group presented the highest number of Lactobacillus spp. copies, followed by the monensin and positive control groups (P > 0.05). Thus, monensin and CNSL-Castor oil effectively minimized the impact of coccidiosis at different times. While monensin acts as an antimicrobial, CNSL-Castor oil modulates the intestinal microbiota with antimicrobial action against gram-positive bacteria, mainly C. perfringens and S. aureus.
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Antiinfecciosos/farmacología , Pollos/inmunología , Microbioma Gastrointestinal/efectos de los fármacos , Monensina/farmacología , Aceites de Plantas/farmacología , Anacardium/química , Alimentación Animal/análisis , Animales , Antiinfecciosos/clasificación , Aceite de Ricino/farmacología , Pollos/crecimiento & desarrollo , Pollos/microbiología , Pollos/fisiología , Coccidiosis/inmunología , Coccidiosis/veterinaria , Dieta/veterinaria , Suplementos Dietéticos/análisis , Eimeria/fisiología , Masculino , Enfermedades de las Aves de Corral/inmunología , Distribución AleatoriaRESUMEN
Infection with Eimeria sp. results in the activation of multiple facets of the host immune system; the use of phytogenics can modulate the inflammatory response and improve the performance of the challenged animal. The aim of this study was to evaluate the effect of a commercial blend of cashew nut shell liquid (CNSL) and castor oil on the immune response of broilers challenged with coccidiosis. A total of 864 one-day-old male chicks (Cobb 500) were randomly distributed into six treatment groups (8 pens/treatment and 18 chicks/pen) in a three-by-two factorial design with three additives: control (non-additive), 100 ppm of monensin or 0.15% CNSL-castor oil. Challenge status was determined twice at 14 days of age. Unchallenged birds were inoculated by gavage with oocysts sporulated with Eimeria tenella, Eimeria acervulina and Eimeria maxima. Although the positive control (non-additive and challenged) and CNSL-castor oil treatment groups exhibited similar variation in weight gain (ΔBWG) compared to unchallenged birds fed without additives, the variation observed in birds fed diets containing CNSL-castor oil was associated with a higher maintenance requirement and not feed efficiency. In the second week after infection, ΔBWG of the CNSL-castor oil treatment group did not significantly change compared to the other treatment groups. At days 7 and 14 post-challenge, there was a higher excretion of oocysts in the control group, whereas the CNSL-castor oil and monensin groups did not differ. The CNSL-castor oil group exhibited increased gene expression of interferon (IFN), interleukin 6 (IL-6) and tumor necrosis factor (TNF), while the control group exhibited increased expression of cyclooxygenase (COX) and IL-1. The heterophils/lymphocyte ratio was low for the monensin treatment group. The unchallenged birds that received monensin treatment presented higher gene expression of IFN, COX and IL-1 compared to the other treatments, while the CNSL-castor oil group exhibited reduced gene expression, except for TNF. The commercial blend of cashew nut liquid and castor oil modulated the inflammatory response against Eimeria spp. In the absence of the parasite, there was no stimulation of genes involved in the inflammatory response, demonstrating that the blend is an effective tool in specifically modulating the immune system of birds afflicted with coccidiosis.
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Anacardium/química , Pollos/inmunología , Coccidiosis/inmunología , Eimeria/fisiología , Aceites de Plantas/administración & dosificación , Enfermedades de las Aves de Corral/inmunología , Alimentación Animal , Animales , Pollos/parasitología , Coccidiosis/parasitología , Dieta/veterinaria , Masculino , Nueces/química , Enfermedades de las Aves de Corral/parasitología , Distribución Aleatoria , Aumento de PesoRESUMEN
BACKGROUND: The quality of colon cleansing and the tolerability of anterograde preparation are essential to the success of colorectal cancer screening. AIM: To compare the tolerability and efficacy of low-volume preparations vs the standard regimen in individuals scheduled for an early morning colonoscopy. Study: Participants in a population-based colorectal cancer screening program using the fecal immunochemical test who were scheduled for a colonoscopy from 09:00 a.m. to 10:20 a.m. were prospectively included and assigned to: (1) control group (PEG-ELS 4L): PEG 4L and electrolytes; (2) group AscPEG-2L: a combination of PEG and ascorbic acid 2L; and (3) group PiMg: sodium picosulfate and magnesium citrate 500 mL plus 2 L of clear fluids. Tolerability was evaluated with a questionnaire and the quality of bowel preparation with the Boston Bowel Preparation Scale. RESULTS: A total of 292 participants were included: 98 in the PEG-ELS 4L control group, 96 in the AscPEG-2L study group and 98 in the PiMg study group. Low-volume treatments were better tolerated than the standard solution (AscPEG-2L 94.8% and PiMg 93.9% vs PEG-ELS 4L 75.5%; p < 0.0001). The effectiveness of AscPEG-2L was superior to that of PEG-ELS 4L and PiMg (p = 0.011 and p = 0.032, respectively). Patient acceptance was higher for single-dose than for split-dose administration but efficacy was higher with the split dose than with other doses. CONCLUSIONS: In early morning colonoscopies, ascPEG-2L appears to be the best option, especially when administered in a split-dose
ANTECEDENTES: La calidad de la limpieza del colon y la tolerancia a la preparación anterógrada son claves para el éxito de un programa de cribado de cáncer colorrectal. OBJETIVO: Comparar la tolerancia y eficacia de las preparaciones de volumen reducido frente a la preparación estándar en pacientes programados para colonoscopia a primera hora de la mañana. Estudio: Individuos del programa de cribado poblacional con test de sangre oculta en heces programados para colonoscopia entre las 09:00 y 10:20 a.m fueron prospectivamente asignados a: 1) Grupo Control (PEG-ELS 4L): PEG con electrolitos 4 litros; 2) Grupo AscPEG-2L: PEG más ácido ascórbico 2 litros; y 3) Groupo PiMg: picosulfato sódico más citrato de magnesio 500 ml seguido de 2 litros de líquidos claros. Se evaluó la tolerancia mediante cuestionario y la calidad mediante la Boston Bowel Preparation Scale. RESULTADOS: Se incluyeron 292 sujetos: 98 en el grupo control PEG-ELS 4L, 96 en el grupo a estudio AscPEG-2L y 98 en el grupo a estudio PiMg. Las soluciones de volumen reducido fueron mejor toleradas que la solución estándar (AscPEG-2L 94.8% y PiMg 93.9% vs PEG-ELS 4L 75.5%; p < 0.0001). La calidad de la preparación fue superior en el grupo AscPEG-2L que en el grupo control PEG-ELS 4L y grupo PiMg (p = 0.011 and p = 0.032, respectivamente). Las dosis partidas fueron peor aceptadas por los sujetos pero resultaron en una mayor calidad de la preparación. CONCLUSIONES: AscPEG-2L es la mejor opción para las colonoscopias programadas a primera hora de la mañana, especialmente cuando se administra en dosis partida
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Humanos , Colonoscopía/métodos , Ácido Ascórbico/administración & dosificación , Neoplasias Colorrectales/diagnóstico , Cuidados Preoperatorios/métodos , Detección Precoz del Cáncer/métodos , Tolerancia a MedicamentosRESUMEN
BACKGROUND: The quality of colon cleansing and the tolerability of anterograde preparation are essential to the success of colorectal cancer screening. AIM: To compare the tolerability and efficacy of low-volume preparations vs the standard regimen in individuals scheduled for an early morning colonoscopy. STUDY: Participants in a population-based colorectal cancer screening program using the fecal immunochemical test who were scheduled for a colonoscopy from 09:00 a.m. to 10:20 a.m. were prospectively included and assigned to: (1) control group (PEG-ELS 4L): PEG 4L and electrolytes; (2) group AscPEG-2L: a combination of PEG and ascorbic acid 2L; and (3) group PiMg: sodium picosulfate and magnesium citrate 500 mL plus 2L of clear fluids. Tolerability was evaluated with a questionnaire and the quality of bowel preparation with the Boston Bowel Preparation Scale. RESULTS: A total of 292 participants were included: 98 in the PEG-ELS 4L control group, 96 in the AscPEG-2L study group and 98 in the PiMg study group. Low-volume treatments were better tolerated than the standard solution (AscPEG-2L 94.8% and PiMg 93.9% vs PEG-ELS 4L 75.5%; p < 0.0001). The effectiveness of AscPEG-2L was superior to that of PEG-ELS 4L and PiMg (p = 0.011 and p = 0.032, respectively). Patient acceptance was higher for single-dose than for split-dose administration but efficacy was higher with the split dose than with other doses. CONCLUSIONS: In early morning colonoscopies, ascPEG-2L appears to be the best option, especially when administered in a split-dose.
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Ácido Ascórbico/análogos & derivados , Catárticos/farmacología , Colonoscopía/métodos , Neoplasias Colorrectales/diagnóstico , Defecación/efectos de los fármacos , Detección Precoz del Cáncer/métodos , Polietilenglicoles/farmacología , Anciano , Ácido Ascórbico/administración & dosificación , Ácido Ascórbico/efectos adversos , Ácido Ascórbico/farmacología , Catárticos/administración & dosificación , Catárticos/efectos adversos , Citratos/administración & dosificación , Citratos/efectos adversos , Citratos/farmacología , Ácido Cítrico/administración & dosificación , Ácido Cítrico/efectos adversos , Ácido Cítrico/farmacología , Mareo/inducido químicamente , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Náusea/inducido químicamente , Compuestos Organometálicos/administración & dosificación , Compuestos Organometálicos/efectos adversos , Compuestos Organometálicos/farmacología , Dolor/inducido químicamente , Aceptación de la Atención de Salud , Picolinas/administración & dosificación , Picolinas/efectos adversos , Picolinas/farmacología , Polietilenglicoles/administración & dosificación , Polietilenglicoles/efectos adversos , Estudios Prospectivos , Encuestas y Cuestionarios , Vómitos/inducido químicamenteRESUMEN
We isolated and identified functional groups of bacteria in the rumen of Creole goats involved in ruminal fermentation of native forage shrubs. The functional bacterial groups were evaluated by comparing the total viable, total anaerobic, cellulolytic, hemicellulolytic, and amylolytic bacterial counts in the samples taken from fistulated goats fed native forage diet (Atriplex lampa and Prosopis flexuosa). Alfalfa hay and corn were used as control diet. The roll tubes method increased the possibility of isolating and 16S rDNA gene sequencing allowed definitive identification of bacterial species involved in the ruminal fermentation. The starch and fiber contents of the diets influenced the number of total anaerobic bacteria and fibrolytic and amylolytic functional groups. Pseudobutyrivibrio ruminis and Pseudobutyrivibrio xylanivorans were the main species isolated and identified. The identification of bacterial strains involved in the rumen fermentation helps to explain the ability of these animals to digest fiber plant cell wall contained in native forage species.
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Alimentación Animal , Dieta/métodos , Bacterias Grampositivas/clasificación , Bacterias Grampositivas/aislamiento & purificación , Rumen/microbiología , Animales , Carga Bacteriana , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Cabras , Bacterias Grampositivas/genética , Bacterias Grampositivas/metabolismo , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
Objetivo. Estimar heredabilidades, correlaciones fenotípicas y genotípicas entre 24 características de tipo y producción de leche en vacas Holstein del departamento de Antioquia. Materiales y métodos. Se analizaron un total de 2395 registros de vacas Holstein. Se estimaron componentes de varianza mediante el procedimiento de máxima verosimilitud restricta con modelos animales bi-característicos. Para las características de tipo, el modelo incluyó los efectos fijos de finca, año de nacimiento y país de origen del padre de la vaca, el grupo contemporáneo (año-mes-clasificador) y la covariable edad a la clasificación. Para la producción de leche el modelo incluyó los efectos fijos de finca, año de parto, país y año de nacimiento del padre. Resultados. Las heredabilidades encontradas para las características de tipo variaron de 0.04 a 0.44 y para producción de leche fue de 0.22, los errores estándar de la heredabilidad fueron inferiores a 0.06. Las correlaciones genéticas de producción de leche con las características profundidad de la ubre (-0.72) fue alta, mientras las correlaciones más altas entre las características de tipo fueron entre extremo anterior y tamaño (0.90), ángulo de la pezuña y profundidad del talón (0.98), profundidad del talón y uniformidad de pezuñas (0.85); y ligamento suspensorio medio y colocación de pezones posteriores (0.76). Conclusiónes. Se encontró una considerable variación genética en características de tipo dentro de la población Holstein de Antioquia. Las correlaciones genéticas entre algunas características de tipo fueron altas e indican la posibilidad de reducir el número de características evaluadas en cada animal.
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Animales , Bovinos , Genética , LecheRESUMEN
AIM: Aberrant crypt foci (ACFs) are clusters of colonic crypts that can be identified after staining and that have a different behaviour than the surrounding crypts. They have been hypothesized to be the potential precursors of colonic neoplastic lesions. Since they are detectable in vivo with endoscopic stains, they have been proposed as early biomarkers for colonic carcinogenesis. Our aim was to examine the literature regarding the role of ACFs in the pathogenesis of colorectal cancer (CRC). METHOD: An intensive PubMed search was performed with the following terms: aberrant crypt foci, colorectal cancer, biomarker, carcinogenesis. RESULTS: Aberrant crypt foci have a variable prevalence and little is known about their natural history. They can be classified as hyperplastic or dysplastic. There is evidence that supports their role as preneoplastic lesions and features detectable by chromoendoscopy have been related to CRC risk. Moreover, ACFs have been shown to harbour genetic and epigenetic alterations common in adenomas and CRC. However, contradictory results have been obtained and difficulties in endoscopic detection and characterization have been described in large-scale studies. CONCLUSION: Despite the inconsistencies in ACF detection and characterization, several genetic and epigenetic changes common in both ACFs and CRC have been verified throughout the studies. This evidence is increasingly strong and it grows along with progress in the knowledge of carcinogenesis molecular pathways. Clinical application of ACFs as an intermediate endpoint for colorectal carcinogenesis is under development and a deeper knowledge of cancer mechanisms is needed before it can be applied or discarded.
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Focos de Criptas Aberrantes/diagnóstico , Neoplasias Colorrectales/diagnóstico , Focos de Criptas Aberrantes/genética , Focos de Criptas Aberrantes/patología , Colonoscopía , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Marcadores Genéticos , HumanosRESUMEN
Los modelos de evaluación genética multirracial permiten la obtención de los valores genéticos de animales perteneciente a una población de diferente composición racial. La estructura de este tipo de modelo va a depender de la característica a evaluar y de la población multirracial a ser analizada, obteniendose al final de la evaluación valores genéticos aditivos y no aditivos, los cuales permiten tomar decisiones y direccionar los apareamientos de una forma más acertada.
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Bovinos , Bovinos , DesteteRESUMEN
The feasibility of a one-step method for the continuous production of astaxanthin by the microalga Haematococcus pluvialis has been verified outdoors. To this end, influence of dilution rate, nitrate concentration in the feed medium, and irradiance on the performance of continuous cultures of H. pluvialis was firstly analyzed indoors in bubble column reactors under daylight cycles, and then outdoors, using a tubular photobioreactor. At the laboratory scale, the behavior of the cultures agreed with that previously recorded in continuous illumination experiences, and attested that the major factors determining biomass and astaxanthin productivity were average irradiance and specific nitrate supply. The rate of astaxanthin accumulation was proportional to the average irradiance inside the culture, provided that a nitrate limiting situation had been established. The accumulation of astaxanthin under daylight cycles was maximal for a specific nitrate input of 0.5 mmol/g day. The recorded performance has been modeled on the basis of previously developed equations, and the validity of the model checked under outdoor conditions. Productivity values for biomass and astaxanthin of 0.7 g/L day and 8.0 mg/L day respectively, were obtained in a pilot scale tubular photobioreactor operating under continuous conditions outdoors. The magnitude of the experimental values, which matched those simulated from the obtained model, demonstrate that astaxanthin can be efficiently produced outdoors in continuous mode through a precise dosage of the specific nitrate input, taking also into consideration the average irradiance inside the culture.
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Reactores Biológicos , Chlorophyta/metabolismo , Chlorophyta/efectos de la radiación , Luz , Chlorophyta/crecimiento & desarrollo , Nitratos/metabolismo , Xantófilas/análisis , Xantófilas/biosíntesisRESUMEN
In this work an optimized method for the extraction of lutein from microalgae biomass is presented. It has been developed using dry biomass of the lutein-rich microalga Scenedesmus almeriensis. The method comprises three steps, cell disruption, alkaline treatment, and solvent extraction, and renders a carotenoid extract rich in lutein. The results demonstrate that cell disruption is necessary and that the best option among the treatments tested with regard to industrial applications is the use of a bead mill with alumina in a 1:1 w/w proportion as disintegrating agent for 5 min. With regard to the alkaline treatment, the optimal conditions were obtained using 4% w/v KOH with a biomass concentration of 100 g/L for 5 min. Longer alkaline treatments or the use of higher KOH concentrations reduced the yield of the process. Finally, extraction with hexane is optimized. Using a 1:1 ratio hexane to sample volume, a total of eight extraction steps are necessary to recover 99% of lutein contained in the processed biomass. However, the optimal number of extraction steps is six, 95% of the lutein being recovered. In summary, the developed method allows the efficient recovery of lutein from microalgae biomass, it being a scaleable and industrially applicable method.
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Biomasa , Fraccionamiento Químico/métodos , Luteína/aislamiento & purificación , Scenedesmus/química , Luteína/análisisRESUMEN
This study was conducted to evaluate if supplementing bypass fat to cows under silvopastoral systems, increases the concentration of unsaturated fatty acids in milk, thus improving the saturated/ unsaturated ratio without a negative effect on total milk yield in fat or protein. Two concentrations of two different sources of bypass fat were evaluated for 40 days, each in a group of 24 multiparous Lucerna (Colombian breed) cows. A cross-over design of 8 Latin squares 3 x 3 was used. The variables submitted to analysis were body condition, daily milk production and milk composition. Body condition, milk yield and milk quality were not different but there was a significant decrease in the amount of saturated fatty acid in both experiments while the unsaturated fat increased significantly in experiment 1 and remained stable in experiment 2. Results, such as these have as far as we know, not been reported previously and they provide an approach for the improvement of milk as a "functional food".
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Bovinos/fisiología , Grasas de la Dieta/administración & dosificación , Ácidos Grasos Insaturados/análisis , Ácidos Grasos/análisis , Lactancia/metabolismo , Proteínas de la Leche/análisis , Leche/química , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Bovinos/metabolismo , Estudios Cruzados , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Femenino , Distribución AleatoriaRESUMEN
In this paper, the biomass and lutein productivity of the lutein-rich new strain Scenedesmus almeriensis is modelled versus irradiance and temperature. The results demonstrate that S. almeriensis is a mesophile microorganism with an optimal growth temperature of 35 degrees C, and capable of withstanding up to 48 degrees C, which caused culture death. This strain is also tolerant to high irradiances, showing no signs of photoinhibition even at the maximum irradiance essayed of 1625 microE m(-2) s(-1) accumulating up to 0.55% dry weight (d.wt.) of lutein. The optimal conditions that maximise the biomass productivity also favour the lutein productivity, lutein being a primary metabolite. Maximal biomass and lutein productivities of 0.87 g l(-1) day(-1) and 4.77 mg l(-1) day(-1), respectively, were measured. The analysis of light availability inside the cultures, quantified as average irradiance, demonstrates that the cultures were mainly photo-limited, although photosaturation also took place at high external irradiances. The effect of temperature was also investigated finding that the specific maximal growth rate is modified by the temperature according to the Arrhenius equation. The influence of both light availability and temperature was included in an overall growth model, which showed, as a result, capable of fitting the whole set of experimental data. An overall lutein accumulation rate model was also proposed and used in a regression analysis. Simulations performed using the proposed models show that under outdoor conditions a biomass productivity of 0.95 g l(-1) day(-1) can be expected, with a lutein productivity up to 5.31 mg l(-1) day(-1). These models may be useful to assist the design and operation optimisation of outdoor cultures of this strain.
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Biomasa , Biotecnología , Técnicas de Cultivo de Célula/métodos , Luteína/metabolismo , Scenedesmus/metabolismo , Scenedesmus/efectos de la radiación , Luz , Modelos Biológicos , Scenedesmus/crecimiento & desarrollo , Scenedesmus/aislamiento & purificación , TemperaturaRESUMEN
Objetivo. Estimar la heredabilidad del intervalo de partos en bovinos cruzados. Materiales y métodos. Se utilizó información de la base de datos de la hacienda La Leyenda, ubicada en el municipio de Caucasia (Antioquia). Se realizó un análisis uni-característico empleando el modelo animal. En el modelo se consideraron los efectos fijos del grupo genético, año de nacimiento, época de nacimiento y el número de partos y como efectos aleatorios, el efecto aditivo directo, de ambiente permanente y residual. Resultados. Se obtuvo una heredabilidad de 0.15 ± 0.07 y una media fenotípica de 544 ± 97 días. Conclusión. La heredabilidad para el intervalo de partos fue baja, por lo que se puede lograr poco progreso genético seleccionando para esta característica.
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Bovinos , Animales , Lactante , Bovinos , Carne , Parto , Parto/genética , Reproducción , Bovinos/crecimiento & desarrollo , Bovinos/genética , Carne/análisis , Carne/microbiología , Reproducción/genéticaRESUMEN
The influence of culture conditions on the quality of Haematococcus pluvialis biomass is assessed. Continuously grown cells have been characterised with respect to their astaxanthin, fatty acid content, and antioxidant activity and compared with those of non-growing haematocysts. Moderate limitation of nitrate availability (1.7 mM) under continuous growth conditions favoured the production of reddish palmelloid cells whose extracts possessed antioxidant activity equivalent to that of haematocyst extracts, despite the lower astaxanthin content (0.6%d.wt.), which is compensated by a higher fatty acid level (7.6%d.wt.). Green cells produced under nitrate saturation conditions (>4.7 mM) exhibit only 40% antioxidant activity than palmelloid. In addition, the major fatty acid present in palmelloid cells was oleic acid (40%f.a.), whereas, in both green cells and haematocysts, the main fatty acids were myristic, palmitic, and oleic acid (20-30%f.a. each). Biomass extracts were fractionated and analysed. The antioxidant capacity was a function of both the carotenoid and the fatty acid profiles, the antioxidant capacity of astaxanthin diesters fraction being 60% higher than astaxanthin monoesters fraction and twice than free astaxanthin. In such a way, the evaluation of the quality of H. pluvialis biomass must take into account both variables. When considering the production of H. pluvialis biomass for human consumption, special attention should be paid to the one-step continuous system approach for the generation of cells rich in both astaxanthin and fatty acids, as they have high antioxidant activity but without thick hard cell wall.
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Antioxidantes/metabolismo , Carotenoides/metabolismo , Chlorophyta/metabolismo , Ácidos Grasos/metabolismo , Xantófilas/metabolismoRESUMEN
No disponible
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Masculino , Adulto , Humanos , Cirrosis Hepática Alcohólica/complicaciones , Peritonitis/etiología , Infecciones Neumocócicas/etiologíaRESUMEN
The adhE gene of Escherichia coli encodes a multifunctional ethanol oxidoreductase (AdhE) that catalyzes successive reductions of acetyl-CoA to acetaldehyde and then to ethanol reversibly at the expense of NADH. Mutant JE52, serially selected for acquired and improved ability to grow aerobically on ethanol, synthesized an AdhE(A267T/E568K) with two amino acid substitutions that sequentially conferred improved catalytic properties and stability. Here we show that the aerobic growth ability on ethanol depends also on protection of the mutant AdhE against metal-catalyzed oxidation by the chaperone DnaK (a member of the Hsp70 family). No DnaK protection of the enzyme is evident during anaerobic growth on glucose. Synthesis of DnaK also protected E. coli from H2O2 killing under conditions when functional AdhE is not required. Our results therefore suggest that, in addition to the known role of protecting cells against heat stress, DnaK also protects numerous kinds of proteins from oxidative damage.