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Background: Academic failure can negatively impact on the student, the university and the nursing workforce in the short term. The aim of this study is to analyze the characteristics and predictors of academic success in two cohorts of students of a Nursing Bachelor's Degree program. Methods: This longitudinal study enrolled students who attended the Nursing Bachelor's Degree program. The Tor Vergata University includes 21 Nursing Bachelor's Degree programs at several Sanitary Institutions of the Rome area, with a mean annual recruitment of 800 students. We considered two cohorts of students beginning the program in the 2011-2012 and 2012-2013 academic years, respectively. The follow-up of these two cohorts ended in the 2017-2018 academic year. We considered socio-demographic and academic variables in the nursing field (pre-admission test grade, training exam grade in the first, second and third year and professional license exam grade). The outcome variable is academic success defined as gradua-tion on time; academic failure is defined as changing degree, delay in completion of the course, attrition and dismissal (failure to complete the studies). Data were collected at baseline (T0), at the end of the first year (T1), at the end of the second year (T2) and at the end of the third year (T3) of the course. A logistic regression was performed to identify predictors of academic success. Results: 2,041 students were enrolled, with an average age of 22.0 years (± 4.6, 18-50); 67.4% were female. Regarding academic success, 30.6% of students graduated on time and so achieved academic success, while 69.4% failed to complete the course within the established time: 5.4% (110/2,041) changed the course, the attrition rate was 7.3%, 0.3% (6/2,041) overdue from the course for expiring of the terms, 18.0% (368/2,041) is attending the course and 38.4% (784/2,041) graduated after more than three years. Pre-admission test grade (OR: 10.0, 95% CI: 10.020-10.054) and training exam grade at the second and third years (OR: 10.0 95% CI: 10.027-10.139; OR: 10.2 95% CI: 10.171-10.294) predicted academic success. Discussion and Conclusions: Some nursing students changed course during the last year of the program, while the training exam grade of the second and third years had predicted academic success; this is a brand new information derived from this study. In addition, we confirmed the association of age, gender, secondary school type and grade and preadmission test with academic success. For these reasons, clinical training should be improved and the quality of internship wards, as learning environments, should be monitored. Italian universities should undertake establishing the ideal cut-off in pre-admission tests to determine which students have a high probability of academic success.
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Éxito Académico , Estudiantes de Enfermería , Adulto , Evaluación Educacional , Femenino , Humanos , Aprendizaje , Estudios Longitudinales , Masculino , Adulto JovenRESUMEN
African swine fever (ASF), one of the most important diseases of swine, has been endemic in the Italian island of Sardinia for more than 35 years. During these decades, several strategies and eradication efforts have been implemented in the island with limited success. Strong climatic and ecological similarities exist between Sardinia and one area of the Iberian Peninsula where Ornithodoros erraticus ticks were involved in the persistence of ASF from 1960 to 1995. This fact leads to the hypothesis that, potentially, Ornithodoros ticks could be also involved in the ASF cycle in Sardinia, thus accounting for some of the reoccurring ASF outbreaks in this island. Initial efforts aimed at detection of Ornithodoros ticks in Sardinia were performed during the 1970s/1980s with no positive results. Accordingly, the absence of Ornithodoros ticks in Sardinia has been generally accepted. However, since a new and reinforced ASF eradication programme has been recently launched in Sardinia, it is essential to clarify the presence and role of these soft ticks in the epizootiology of ASF in this island. For that purpose, 1767 porcine serum samples collected from all around the island (1261 from domestic and 506 from wild boar) were analysed by ELISA for antibodies to salivary antigens of Ornithodoros erraticus. In addition, Ornithodoros ticks were directly searched in a number of pig premises that have suitable habitats for these ticks and were located in areas repeatedly affected by ASF. Only one serum sample resulted positive in the serological assay, and no Ornithodoros ticks were collected in none of the premises. These results indicate that these soft tick species are not involved in the epizootic cycle of ASF in Sardinia and highlight the importance of controlling other risk factors still present in the island for effectively eradicate the disease.
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Fiebre Porcina Africana/prevención & control , Distribución Animal , Ornithodoros/fisiología , Animales , Antígenos/aislamiento & purificación , Italia , Saliva/química , PorcinosRESUMEN
BACKGROUND: This study examines the microbial and fungal contamination associated with the presence of renovation works in a hospital site in Sardinia (Italy). METHODS: Microbiological environmental monitoring was carried out before, during and at the conclusion of the works in the Ophthalmology Department in view of a risk assessment procedure. RESULTS: Although the median values of microbial and fungal counts were found raised during the works, protective measures set out by the internal procedures limited the contamination level. CONCLUSIONS: This study emphasizes the benefits of environmental surveillance for airborne contamination to help prevent outbreaks of nosocomial mycosis associated with construction work.
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Microbiología del Aire , Monitoreo del Ambiente , Hospitales , Micosis , Infección Hospitalaria , Humanos , ItaliaRESUMEN
The 2011 Tohoku earthquake (Mw = 9.1) highlighted previously unobserved features for megathrust events, such as the large slip in a relatively limited area and the shallow rupture propagation. We use a Finite Element Model (FEM), taking into account the 3D geometrical and structural complexities up to the trench zone, and perform a joint inversion of tsunami and geodetic data to retrieve the earthquake slip distribution. We obtain a close spatial correlation between the main deep slip patch and the local seismic velocity anomalies, and large shallow slip extending also to the North coherently with a seismically observed low-frequency radiation. These observations suggest that the friction controlled the rupture, initially confining the deeper rupture and then driving its propagation up to the trench, where it spreads laterally. These findings are relevant to earthquake and tsunami hazard assessment because they may help to detect regions likely prone to rupture along the megathrust, and to constrain the probability of high slip near the trench. Our estimate of ~40 m slip value around the JFAST (Japan Trench Fast Drilling Project) drilling zone contributes to constrain the dynamic shear stress and friction coefficient of the fault obtained by temperature measurements to ~0.68 MPa and ~0.10, respectively.
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The 2011 Tohoku-oki (Mw 9.1) earthquake is so far the best-observed megathrust rupture, which allowed the collection of unprecedented offshore data. The joint inversion of tsunami waveforms (DART buoys, bottom pressure sensors, coastal wave gauges, and GPS-buoys) and static geodetic data (onshore GPS, seafloor displacements obtained by a GPS/acoustic combination technique), allows us to retrieve the slip distribution on a non-planar fault. We show that the inclusion of near-source data is necessary to image the details of slip pattern (maximum slip ~48â m, up to ~35â m close to the Japan trench), which generated the large and shallow seafloor coseismic deformations and the devastating inundation of the Japanese coast. We investigate the relation between the spatial distribution of previously inferred interseismic coupling and coseismic slip and we highlight the importance of seafloor geodetic measurements to constrain the interseismic coupling, which is one of the key-elements for long-term earthquake and tsunami hazard assessment.
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Amphipols (APols) are short amphipathic polymers that can substitute for detergents to keep integral membrane proteins (MPs) water soluble. In this review, we discuss their structure and solution behavior; the way they associate with MPs; and the structure, dynamics, and solution properties of the resulting complexes. All MPs tested to date form water-soluble complexes with APols, and their biochemical stability is in general greatly improved compared with MPs in detergent solutions. The functionality and ligand-binding properties of APol-trapped MPs are reviewed, and the mechanisms by which APols stabilize MPs are discussed. Applications of APols include MP folding and cell-free synthesis, structural studies by NMR, electron microscopy and X-ray diffraction, APol-mediated immobilization of MPs onto solid supports, proteomics, delivery of MPs to preexisting membranes, and vaccine formulation.
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Proteínas de la Membrana/química , Proteínas de la Membrana/ultraestructura , Modelos Químicos , Modelos Moleculares , Polímeros/química , Sitios de Unión , Simulación por Computador , Unión ProteicaRESUMEN
The determination of rock friction at seismic slip rates (about 1 m s(-1)) is of paramount importance in earthquake mechanics, as fault friction controls the stress drop, the mechanical work and the frictional heat generated during slip. Given the difficulty in determining friction by seismological methods, elucidating constraints are derived from experimental studies. Here we review a large set of published and unpublished experiments (â¼300) performed in rotary shear apparatus at slip rates of 0.1-2.6 m s(-1). The experiments indicate a significant decrease in friction (of up to one order of magnitude), which we term fault lubrication, both for cohesive (silicate-built, quartz-built and carbonate-built) rocks and non-cohesive rocks (clay-rich, anhydrite, gypsum and dolomite gouges) typical of crustal seismogenic sources. The available mechanical work and the associated temperature rise in the slipping zone trigger a number of physicochemical processes (gelification, decarbonation and dehydration reactions, melting and so on) whose products are responsible for fault lubrication. The similarity between (1) experimental and natural fault products and (2) mechanical work measures resulting from these laboratory experiments and seismological estimates suggests that it is reasonable to extrapolate experimental data to conditions typical of earthquake nucleation depths (7-15 km). It seems that faults are lubricated during earthquakes, irrespective of the fault rock composition and of the specific weakening mechanism involved.
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The metabolic profiling of kiwifruit (Actinidia deliciosa, Hayward cultivar) aqueous extracts and the water status of entire kiwifruits were monitored over the season (June-December) using nuclear magnetic resonance (NMR) methodologies. The metabolic profiling of aqueous kiwifruit extracts was investigated by means of high field NMR spectroscopy. A large number of water-soluble metabolites were assigned by means of 1D and 2D NMR experiments. The change in the metabolic profiles monitored over the season allowed the kiwifruit development to be investigated. Specific temporal trends of aminoacids, sugars, organic acids and other metabolites were observed. The water status of kiwifruits was monitored directly on the intact fruit measuring the T(2) spin-spin relaxation time by means of a portable unilateral NMR instrument, fully non-invasive. Again, clear trends of the relaxation time were observed during the monitoring period. The results show that the monitoring of the metabolic profiling and the monitoring of the water status are two complementary means suitable to have a complete view of the investigated fruit.
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Actinidia/metabolismo , Análisis de los Alimentos/métodos , Frutas/química , Espectroscopía de Resonancia Magnética/métodos , Agua/análisis , Actinidia/crecimiento & desarrollo , Aminoácidos/análisis , Carbohidratos/análisis , Ácidos Carboxílicos/análisis , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Italia , Extractos Vegetales/química , Estaciones del AñoRESUMEN
The molecular feature of Burkitt lymphoma (BL) is the translocation that places c-Myc under the control of immunoglobulin gene regulatory elements. However, there is accumulating evidence that some cases may lack an identifiable MYC translocation. In addition, during the EUROFISH project, aiming at the standardization of FISH procedures in lymphoma diagnosis, we found that five cases out of 35 classic endemic BLs were negative for MYC translocations by using a split-signal as well as a dual-fusion probe. Here we investigated the expression pattern of miRNAs predicted to target c-Myc, in BL cases, to clarify whether alternative pathogenetic mechanisms may be responsible for lymphomagenesis in cases lacking the MYC translocation. miRNAs are a class of small RNAs that are able to regulate gene expression at the post-transcriptional level. Several studies have reported their involvement in cancer and their association with fragile sites in the genome. They have also been shown to control cell growth, differentiation, and apoptosis, suggesting that these molecules could act as tumour suppressors or oncogenes. Our results demonstrated a modulation of specific miRNAs. In particular, down-regulation of hsa-let-7c was observed in BL cases, compared to normal controls. More interestingly, hsa-mir-34b was found to be down-regulated only in BL cases that were negative for MYC translocation, suggesting that this event might be responsible for c-Myc deregulation in such cases. This hypothesis was further confirmed by our in vitro experiments, which demonstrated that increasing doses of synthetic hsa-mir-34b were able to modulate c-Myc expression. These results indicate for the first time that hsa-mir-34b may influence c-Myc expression in Burkitt lymphoma as the more common aberrant control exercised by the immunoglobulin enhancer locus.
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Linfoma de Burkitt/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Adolescente , Adulto , Linfoma de Burkitt/patología , Niño , Preescolar , Femenino , Expresión Génica , Genes de Inmunoglobulinas , Genes myc , Humanos , Hibridación Fluorescente in Situ/métodos , Masculino , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Translocación Genética , Adulto JovenRESUMEN
BACKGROUND: Amiodarone-induced thyrotoxicosis (AIT) is caused by excessive hormone synthesis and release (AIT I) or a destructive process (AIT II). This differentiation has important therapeutic implications. PURPOSE: To evaluate (99m)Tc-sestaMIBI (MIBI) thyroid scintigraphy in addition to other diagnostic tools in the diagnosis and management of AIT. SUBJECTS AND METHODS: Thyroid and (99m)Tc-MIBI scintigraphies were performed in 20 consecutive AIT patients, along with a series of biochemical and instrumental investigations (measurement of thyrotrophin, free thyroid hormones and thyroid autoantibodies; thyroid colour-flow Doppler sonography (CFDS) and thyroid radioiodine uptake (RAIU)). RESULTS: On the basis of instrumental and laboratory data (excluding thyroid (99m)Tc-MIBI scintigraphy) and follow-up, AIT patients could be subdivided into six with AIT I, ten with AIT II and four with indefinite forms of AIT (AIT Ind). (99m)Tc-MIBI uptake results were normal/increased in all the six patients with AIT I and absent in all the ten patients with AIT II. The remaining four patients with AIT Ind showed low, patchy and persistent uptake in two cases and in the other two evident MIBI uptake followed by a rapid washout. MIBI scintigraphy was superior to all other diagnostic tools, including CFDS (suggestive of AIT I in three patients with AIT II and of AIT II in three with AIT Ind) and RAIU, which was measurable in all patients with AIT I, and also in four out of the ten with AIT II. CONCLUSION: Thyroid MIBI scintigraphy may be proposed as an easy and highly effective tool for the differential diagnosis of different forms of AIT.
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Amiodarona/efectos adversos , Antiarrítmicos/efectos adversos , Radiofármacos , Tecnecio Tc 99m Sestamibi , Tirotoxicosis/inducido químicamente , Tirotoxicosis/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Fibrilación Atrial/tratamiento farmacológico , Aleteo Atrial/tratamiento farmacológico , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Radioisótopos de Yodo , Masculino , Persona de Mediana Edad , Cintigrafía , Ultrasonografía Doppler en ColorAsunto(s)
Enfermedades Fetales , Infecciones , Complicaciones Infecciosas del Embarazo , Infecciones por Citomegalovirus/diagnóstico , Infecciones por Citomegalovirus/terapia , Femenino , Enfermedades Fetales/diagnóstico , Enfermedades Fetales/terapia , Herpes Simple/diagnóstico , Herpes Simple/terapia , Humanos , Recién Nacido , Infecciones/diagnóstico , Infecciones/terapia , Obstetricia , Embarazo , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/terapia , Rubéola (Sarampión Alemán)/diagnóstico , Rubéola (Sarampión Alemán)/terapia , Toxoplasmosis/diagnóstico , Toxoplasmosis/terapiaRESUMEN
The complete assignment of the 1H and 13C NMR spectra of bendaline (BNDL) was performed by mono-dimensional and homo- and hetero-correlated two-dimensional NMR experiments. The interaction between bendaline and albumin was also studied by the analysis of the motional parameters spin-lattice relaxation times, allowing the motional state of the BNDL free and bound with albumin to be defined. In absence of albumin the indazolacetic and benzylic moieties are characterized by roughly the same mobility and by positive sigma (cross-relaxation rates) values. In the presence of the macromolecule, the indazolacetic and benzylic moieties and the lysine change their motional behaviour to different extents, as indicated by correlation times. Data obtained in absence and in presence of the protein show that the molecular moiety of the bendaline most involved in the binding with albumin is the fragment H-4 H-5. The binding constant was evaluated at 2.4x10(3)M(-1).
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Indazoles/química , Albúmina Sérica/química , Sitios de Unión , Isótopos de Carbono , Relación Dosis-Respuesta a Droga , Humanos , Espectroscopía de Resonancia Magnética , Estructura Molecular , ProtonesRESUMEN
A series of 6-thioxopyrimidines (5, 6), their 6-oxo- analogs (11-14), and pyrimidine-2,4-diones (20-26), were synthesized and evaluated for their antitumoral activity against 60 tumoral cell lines. The activity of propenethioamide (3, 4) and propeneamide (7-10 and 15-19) intermediates is also reported. Among the tested compounds the thioxopyrimidine 5c, bearing an N'-benzyl group, showed the best cytostatic activity. Furthermore, high selectivity and cytotoxic activity on the HOP-92 cell line of non-small cell lung cancer was exhibited by 3-amino-2-[(methylamino)thioxamethyl]-3-pyrrolidino-2-propenenitrile (3a).
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Antineoplásicos/síntesis química , Neoplasias/tratamiento farmacológico , Pirimidinas/síntesis química , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Química Farmacéutica , Humanos , Pirimidinas/química , Pirimidinas/uso terapéutico , Relación Estructura-Actividad , Células Tumorales CultivadasRESUMEN
4-(2-Pyridinylamino)-1,1,1-trifluoro-3-penten-2-ones 3, obtained from the reaction of commercially available 2-aminopyridine derivatives and 4-methoxy-1,1,1-trifluoro-3-penten-2-one 2, were converted to 6-(dimethylamino)-4-(2-pyridinylamino)-3,5-hexadien-2-ones 4 by treatment with dimethylformamide dimethyl acetal. Azannulation of hexadienones 4 afforded 4-(2-pyridinylamino)-2-trifluoromethylpyridines 5 and 2-(trifluoroacetylmethylene)pyrido[1,2-a]pyrimidines 6, classes of compounds particularly interesting from a chemical and biological point of view.
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Piridinas/química , Piridinas/síntesis química , Espectroscopía de Resonancia MagnéticaRESUMEN
Although membrane proteins and soluble proteins may achieve their final folded states through different pathways, it has been suggested that the packing inside a membrane protein could maintain a similar fold if the lipid-exposed surface were redesigned for solubility in an aqueous environment. To test this idea, the surface of the transmembrane domain of phospholamban (PLB), a protein that forms a stable helical homopentamer within the sarcoplasmic reticulum membrane, has been redesigned by replacing its lipid-exposed hydrophobic residues with charged and polar residues. CD spectra indicate that the full-length soluble PLB is highly alpha-helical. Small-angle X-ray scattering and multiangle laser light scattering experiments reveal that this soluble variant of PLB associates as a pentamer, preserving the oligomeric state of the natural protein. Mutations that destabilize native PLB also disrupt the pentamer. However, NMR experiments suggest that the redesigned protein exhibits molten globule-like properties, possibly because the redesign of the surface of this membrane protein may have altered some native contacts at the core of the protein or possibly because the core is not rigidly packed in wild-type PLB. Nonetheless, our success in converting the membrane protein PLB into a specific soluble helical pentamer indicates that the interior of a membrane protein contains at least some of the determinants necessary to dictate folding in an aqueous environment. The design we successfully used was based on one of the two models in the literature; the alternative design did not give stable, soluble pentamers. This suggests that surface redesign can be employed in gaining insights into the structures of membrane proteins.
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Proteínas de Unión al Calcio/química , Proteínas de Unión al Calcio/síntesis química , Ingeniería de Proteínas/métodos , Pliegue de Proteína , Secuencia de Aminoácidos , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/aislamiento & purificación , Dicroismo Circular , Rayos Láser , Datos de Secuencia Molecular , Resonancia Magnética Nuclear Biomolecular , Estructura Secundaria de Proteína , Proteínas Recombinantes de Fusión/síntesis química , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/aislamiento & purificación , Dispersión de Radiación , Solubilidad , Rayos XRESUMEN
Through the concept of memory by Walter Benjamin, the authors of the present study identify relevant facts of the Brazilian Association of Nursing (ABEn) that affected the development of nursing in Brazil. The investigation points out the participation of ABEn in the regulation of the nursing field, creation of Revista Brasileira de Enfermagem (Brazilian Journal of Nursing), promotion of the Congressos Brasileiros de Enfermagem (Brazilian Congresses of Nursing) and its importance on the political struggle for better health conditions in Brazil.
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Enfermería/tendencias , Sociedades de Enfermería/historia , Brasil , Historia de la Enfermería , Historia del Siglo XX , Legislación de Enfermería/historia , Enfermería/organización & administración , Filosofía en Enfermería/historia , Publicaciones/historiaRESUMEN
4-hydroxy-2-pyridone derivatives 2 were prepared by reaction of 3-amino-3-dialkylaminopropenoates with bis(2,4, 6-trichlorophenyl)malonate. These compounds were further reacted with a set of aldehydes to give bis(pyridyl)methanes 3 and 4. The newly synthesized compounds 2, 3 and 4 were evaluated in vitro as antitumour agents against 60 human tumour cell lines. Some derivatives exhibit tumour growth inhibition activity. In particular, derivative 4g, the most active of the series, possesses significant activity on all cell lines at concentrations ranging from 1 x 10(-6) to 1 x 10(-5) M.
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Antineoplásicos/síntesis química , Morfolinas/síntesis química , Piridonas/síntesis química , Antineoplásicos/farmacología , Humanos , Estructura Molecular , Morfolinas/farmacología , Piridinas/química , Piridonas/farmacología , Células Tumorales CultivadasRESUMEN
Changes in brain lipid composition have been determined in 24 months-old Fischer rats with respect to 6 months-old ones. The cerebral levels of sphingomyelin and cholesterol were found to be significantly increased in aged rats, whereas the amount of phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, and phosphatidic acid appear to be unaffected by aging. Long-term feeding with acetyl-L-carnitine was able to reduce the age-dependent increase of both sphingomyelin and cholesterol cerebral levels with no effect on the other measured phospholipids. These findings shown that changes in membrane lipid metabolism and/or composition represent one of the alterations occurring in rat brain with aging, and that long-term feeding with acetyl-L-carnitine can be useful in normalizing these age-dependent disturbances.
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Acetilcarnitina/farmacología , Envejecimiento/metabolismo , Encéfalo/metabolismo , Metabolismo de los Lípidos , Nootrópicos/farmacología , Animales , Lípidos/química , Espectroscopía de Resonancia Magnética , Masculino , Ratas , Ratas Endogámicas F344 , Esfingomielinas/metabolismoRESUMEN
Polar residues in transmembrane alpha-helices may strongly influence the folding or association of integral membrane proteins. To test whether a motif that promotes helix association in a soluble protein could do the same within a membrane, we designed a model transmembrane helix based on the GCN4 leucine zipper. We found in both detergent micelles and biological membranes that helix association is driven strongly by asparagine, independent of the rest of the hydrophobic leucine and/or valine sequence. Hydrogen bonding between membrane helices gives stronger associations than the packing of surfaces in glycophorin A helices, creating an opportunity to stabilize structures, but also implying a danger that non-specific interactions might occur. Thus, membrane proteins may fold to avoid exposure of strongly hydrogen bonding groups at their lipid exposed surfaces.
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Proteínas de Unión al ADN , Proteínas de la Membrana/química , Proteínas de Saccharomyces cerevisiae , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Asparagina/química , Membrana Celular/metabolismo , Cloranfenicol O-Acetiltransferasa/química , Cloranfenicol O-Acetiltransferasa/genética , Cloranfenicol O-Acetiltransferasa/metabolismo , Dicroismo Circular , Detergentes/química , Dimerización , Electroforesis en Gel de Poliacrilamida , Proteínas Fúngicas/química , Glicoforinas/química , Glicoforinas/genética , Glicoforinas/metabolismo , Enlace de Hidrógeno , Leucina Zippers , Espectroscopía de Resonancia Magnética , Proteínas de la Membrana/metabolismo , Micelas , Nucleasa Microcócica/química , Datos de Secuencia Molecular , Péptidos/química , Conformación Proteica , Proteínas Quinasas/química , Estructura Secundaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMEN
We studied the effect of continuous medium flow on the viabilityand structural organization of hepatocytes high density entrapped inalginate gel beads in the first few hours after isolation.The metabolic energy status of the entrapped cells, monitored invivo by (31)P NMR spectroscopy, was stable during theexperimental time and a physiological redox ratio was reachedafter the first three hours of culture. The morphologicalanalysis revealed that the entrapped hepatocytes placed in a fixed-bed bioreactor under continuous flow showed a polyhedricalshape with numerous microvilli on cell surface and reconstitutedtight junctions as well as bile canalicular structures, closelyresembling those present in the liver.These results suggest that continuous flow allows the culture ofhepatocytes at very high cell density within a matrix withoutloss of viability and accelerates cellular tissue reconstructionat very short times after isolation. This type of culture couldrepresent a very useful model for physiological andtoxicological studies as well as a promising approach toward thedevelopment of a bioartificial hybrid support device in acuteliver failure.