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1.
Epidemiol Infect ; 144(15): 3148-3165, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27412705

RESUMEN

The incursion of influenza A(H1N1)pdm09 virus was detected by Norway's active serosurveillance of its pig population in 2009. Since then, surveillance data from 2010 to 2014 revealed that 54% of 5643 herd tests involving 1567 pig herds and 28% of 23 036 blood samples screened positive for antibodies against influenza A virus. Positive herds were confirmed to have influenza A(H1N1)pdm09 virus infection by haemagglutination inhibition test. In 50% of positive herd tests, ⩾60% of the sampled pigs in each herd had antibodies against influenza A(H1N1)pdm09 virus. This within-herd animal seroprevalence did not vary for type of production, herd size or year of test. The overall running mean of national herd seroprevalence, and annual herd incidence risks fluctuated narrowly around the means of 45% and 32%, respectively, with the highest levels recorded in the three densest pig-producing counties. The probability of a herd being seropositive varied in the five production classes, which were sow pools, multiplier herds, conventional sow herds, nucleus herds, and fattening herds in descending order of likelihood. Large herds were more likely to be seropositive. Seropositive herds were highly likely to be seropositive the following year. The study shows that influenza A(H1N1)pdm09 virus is established in the Norwegian pig population with recurrent and new herd infections every year with the national herd seroprevalence in 2014 hovering at around 43% (95% confidence interval 40-46%).


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/aislamiento & purificación , Infecciones por Orthomyxoviridae/epidemiología , Enfermedades de los Porcinos/epidemiología , Mataderos , Animales , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Incidencia , Noruega/epidemiología , Infecciones por Orthomyxoviridae/virología , Prevalencia , Estudios Seroepidemiológicos , Porcinos , Enfermedades de los Porcinos/virología
2.
J Fish Dis ; 38(4): 343-53, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24661057

RESUMEN

Pancreas disease (PD) in Norwegian salmonid aquaculture has traditionally been caused by salmonid alphavirus (SAV) subtype 3. Following the isolation of a novel SAV subtype in 2010, marine SAV2, two separate endemic areas have developed. It has been debated whether disease outbreaks due to marine SAV2 result in milder clinical manifestations compared to outbreaks caused by SAV3. The aim of this study was to descriptively investigate site-level differences in the clinical manifestations of marine SAV2 and SAV3 at Norwegian seawater sites diagnosed with PD in 2012. The findings suggest that Norwegian PD outbreaks caused by marine SAV2 result in lower mortality and milder clinical signs compared to outbreaks caused by SAV3. For sites without reported PD-related mortality, there was no difference in the mortality levels between sites infected by marine SAV2 and SAV3. The results also indicate that there are no differences in grading quality at slaughter between the SAV subtypes.


Asunto(s)
Infecciones por Alphavirus/veterinaria , Alphavirus/clasificación , Alphavirus/fisiología , Brotes de Enfermedades/veterinaria , Enfermedades de los Peces/patología , Enfermedades de los Peces/virología , Enfermedades Pancreáticas/veterinaria , Alphavirus/aislamiento & purificación , Infecciones por Alphavirus/mortalidad , Infecciones por Alphavirus/patología , Infecciones por Alphavirus/prevención & control , Infecciones por Alphavirus/virología , Animales , Acuicultura , Brotes de Enfermedades/prevención & control , Enfermedades de los Peces/mortalidad , Enfermedades de los Peces/prevención & control , Noruega , Enfermedades Pancreáticas/mortalidad , Enfermedades Pancreáticas/patología , Enfermedades Pancreáticas/prevención & control , Enfermedades Pancreáticas/virología
4.
Geroscience ; 44(2): 639-650, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35129777

RESUMEN

Osteoarthritis (OA) is a chronic degenerative disease characterized by a disruption of articular joint cartilage homeostasis. Mice are the most commonly used models to study OA. Despite recent reviews, there is still a lack of knowledge about the new development in imaging techniques. Two types of modalities are complementary: those that assess structural changes in joint tissues and those that assess metabolism and disease activity. Micro MRI is the most important imaging tool for OA research. Automated methodologies for assessing periarticular bone morphology with micro-CT have been developed allowing quantitative assessment of tibial surface that may be representative of the whole OA joint changes. Phase-contrast X-ray imaging provides in a single examination a high image precision with good differentiation between all anatomical elements of the knee joint (soft tissue and bone). Positron emission tomography, photoacoustic imaging, and fluorescence reflectance imaging provide molecular and functional data. To conclude, innovative imaging technologies could be an alternative to conventional histology with greater resolution and more efficiency in both morphological analysis and metabolism follow-up. There is a logic of permanent adjustment between innovations, 3R rule, and scientific perspectives. New imaging associated with artificial intelligence may add to human clinical practice allowing not only diagnosis but also prediction of disease progression to personalized medicine.


Asunto(s)
Cartílago Articular , Osteoartritis de la Rodilla , Animales , Inteligencia Artificial , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/patología , Modelos Animales de Enfermedad , Articulación de la Rodilla/patología , Ratones , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/patología , Microtomografía por Rayos X/métodos
5.
Phys Med Biol ; 66(17)2021 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-34412046

RESUMEN

X-ray phase contrast imaging (PCI) denotes a group of highly sensitive imaging techniques that permits imaging at scales ranging from nanoscopic to the medical. Recently introduced, speckle-based imaging has seen a rapid development because of its experimental simplicity and its capability to retrieve the refraction, the scattering and the absorption of a sample using a conventional x-ray set-up. Precise simulation would permit to optimise the imaging setups for different applications, but until now works on simulation of x-ray speckle-based PCI have been very few. In this work we evaluate different simulation codes, based on Monte-Carlo, analytical ray-tracing and wave-optics Fresnel propagation. The simulation results are compared to both synchrotron and conventional imaging experiments to permits their validation. We obtain a strong similarity between simulated and experimental data. We discuss the validity and applicability of each approach.


Asunto(s)
Rayos X , Simulación por Computador , Método de Montecarlo , Radiografía , Sincrotrones
6.
J Fish Dis ; 33(5): 391-402, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20158578

RESUMEN

A cohort study was initiated in the spring of 2006 to investigate epidemiological aspects and pathogenesis of salmonid alphavirus (SAV) subtype 3 infections and pancreas disease (PD). The aims were to assess involvement of the freshwater production phase, the extent and frequency of subclinical infections and to follow PD-affected populations throughout the entire seawater production cycle, as well as investigate possible risk factors for PD outbreaks. Fish groups from 46 different Atlantic salmon freshwater sites in six counties were sampled once prior to seawater transfer and followed onto their seawater sites. A total of 51 Atlantic salmon seawater sites were included, and fish groups were sampled three times during the seawater production phase. SAV subtype 3 was not identified by real-time RT-PCR from samples collected in the freshwater phase, nor were any SAV-neutralizing antibodies or histopathological changes consistent with PD. In the seawater phase, SAV was detected in samples from 23 of 36 (63.9%) studied sites located within the endemic region. No SAV subtype 3 was detected in samples from seawater sites located outside the endemic region. The cumulative incidence of PD during the production cycle amongst sites with SAV detected was 87% (20 of 23 sites). Average fish weight at time of PD diagnosis ranged from 461 to 5978 g, because of a wide variation in the timing of disease occurrence throughout the production cycle. Mortality levels following a PD diagnosis varied greatly between populations. The mean percentage mortality was 6.9% (+/-7.06) (range 0.7-26.9), while the mean duration of increased mortality following PD diagnosis was 2.8 months (+/-1.11) (range 1-6).


Asunto(s)
Infecciones por Alphavirus/veterinaria , Enfermedades de los Peces/epidemiología , Enfermedades de los Peces/patología , Agua Dulce , Enfermedades Pancreáticas/veterinaria , Agua de Mar , Alphavirus , Infecciones por Alphavirus/epidemiología , Infecciones por Alphavirus/mortalidad , Infecciones por Alphavirus/patología , Animales , Anticuerpos Antivirales/sangre , Estudios de Cohortes , Enfermedades de los Peces/mortalidad , Enfermedades de los Peces/virología , Incidencia , Estimación de Kaplan-Meier , Noruega , Enfermedades Pancreáticas/epidemiología , Enfermedades Pancreáticas/mortalidad , Enfermedades Pancreáticas/patología , Enfermedades Pancreáticas/virología , Reacción en Cadena de la Polimerasa , Prevalencia , Factores de Riesgo , Salmo salar
7.
Euro Surveill ; 14(45)2009 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-19941789

RESUMEN

In Norway there is an ongoing outbreak in pigs of infections with pandemic influenza A(H1N1)v virus. The first herd was confirmed positive on 10 October 2009. As of 26 October, a total of 23 herds have been diagnosed as positive. The majority of the herds seem to have been infected by humans. Sequence analysis of pig viruses from the index farm shows that they are identical or virtually identical to human viruses from the same geographical region.


Asunto(s)
Brotes de Enfermedades/veterinaria , Subtipo H1N1 del Virus de la Influenza A/aislamiento & purificación , Gripe Humana/virología , Infecciones por Orthomyxoviridae/veterinaria , Enfermedades de los Porcinos/transmisión , Animales , Brotes de Enfermedades/prevención & control , Femenino , Humanos , Gripe Humana/transmisión , Masculino , Cavidad Nasal/virología , Noruega/epidemiología , Infecciones por Orthomyxoviridae/prevención & control , Infecciones por Orthomyxoviridae/transmisión , Sus scrofa , Porcinos , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/prevención & control
8.
Int J Clin Pharmacol Ther ; 46(2): 102-8, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18218291

RESUMEN

UNLABELLED: Deferasirox (ExjadeA, ICL670) is a new, once-daily oral iron chelator, recently approved as first-line therapy in the treatment of iron overload resulting from blood transfusions. In registration studies, deferasirox tablets were dispersed in non-carbonated water prior to administration. In routine clinical practice, however, patients may prefer to take the tablet dispersed in a flavored drink rather than with water. OBJECTIVE: Stability and compatibility tests were performed to identify beverages suitable for the dispersion of tablets for further testing in man. This was followed by a pharmacokinetic study to assess the relative bioavailability of deferasirox tablets dispersed in two types of soft drinks, dispersed in water, and without dispersion. METHODS: An open-label, randomized, 4-period, crossover study was carried out with 28 healthy volunteers who received single 20 mg/kg oral doses of deferasirox without dispersion, dispersed in orange juice, dispersed in apple juice and dispersed in non-carbonated water (reference). Deferasirox and Fe-[deferasirox]2 were measured in plasma using liquid chromatography-mass spectrometry. Pharmacokinetic parameters were compared using standard bioequivalence tests. RESULTS: Mean deferasirox AUC0-t were 1,040 A+/- 530, 1,010 A+/- 278, 882 A+/- 252 and 996 A+/- 352 h x micromol/l when deferasirox tablets were administered without dispersion, dispersed in orange juice, dispersed in apple juice and dispersed in water, respectively, indicating that these forms of deferasirox administrations met bioequivalence criteria. Therefore, the oral bioavailability of deferasirox tablets was not affected neither by the degree of dispersion nor by the type of drink (orange or apple juice versus water) used for dispersion. CONCLUSIONS: This study shows that deferasirox bioavailability is unaltered when dispersed with orange or apple juice compared with dispersion in water. Thus, in addition to water, patients have the option of taking deferasirox tablets in orange or apple juice. The degree of dispersion did not affect deferasirox bioavailability. Therefore, deferasirox therapy will not be compromised if dispersion of the tablet is not fully complete; although the latter should be avoided.


Asunto(s)
Benzoatos/farmacocinética , Bebidas , Triazoles/farmacocinética , Agua/química , Administración Oral , Adulto , Área Bajo la Curva , Benzoatos/sangre , Benzoatos/química , Disponibilidad Biológica , Cromatografía Líquida de Alta Presión , Citrus sinensis , Estudios Cruzados , Deferasirox , Diarrea/inducido químicamente , Estabilidad de Medicamentos , Semivida , Humanos , Quelantes del Hierro/administración & dosificación , Quelantes del Hierro/efectos adversos , Quelantes del Hierro/farmacocinética , Masculino , Malus , Comprimidos , Espectrometría de Masas en Tándem , Triazoles/sangre , Triazoles/química , Agua/administración & dosificación
9.
Prev Vet Med ; 84(3-4): 213-27, 2008 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-18243376

RESUMEN

Epidemiological information was summarized from 32 outbreaks of infectious salmon anaemia (ISA) on salmon farming sites in Norway in 2003-2005. Virus isolates from the outbreak sites were genotyped, and the genotyping was used to assess possible associations between outbreak sites due to adjacent location, sharing fish farming authorisation, sharing smolt suppliers or sharing broodfish origin of the fish. The ISA outbreaks were distributed along most of the Norwegian coast and showed a variable clinical picture. The virus genotypes clustered into three genogroups. Pairs of outbreak sites matched for adjacent location or registered under the same authorisation, all shared genogroup, which was a significantly higher number of corresponding genogroups than expected by chance. For outbreak sites sharing smolt suppliers, corresponding genogroups appeared in 7 out of 12 matched pairs, which was not significant. An evaluation of broodfish origin associated with genogroups did not support transmission linked to broodfish origin. In conclusion, genotyping of virus isolates from ISA outbreaks supports associations between adjacent outbreaks. This is consistent with horizontal transmission. The present study failed to find evidence for vertical transmission (patterns of genogroups related to smolt suppliers or broodfish companies were not identified).


Asunto(s)
Brotes de Enfermedades/veterinaria , Enfermedades de los Peces/epidemiología , Isavirus/aislamiento & purificación , Infecciones por Orthomyxoviridae/veterinaria , Salmo salar/virología , Animales , Transmisión de Enfermedad Infecciosa/veterinaria , Enfermedades de los Peces/transmisión , Enfermedades de los Peces/virología , Explotaciones Pesqueras , Genotipo , Isavirus/clasificación , Isavirus/genética , Noruega/epidemiología , Infecciones por Orthomyxoviridae/epidemiología , Infecciones por Orthomyxoviridae/transmisión , Reacción en Cadena de la Polimerasa , Factores de Riesgo , Encuestas y Cuestionarios , Virus/genética , Virus/aislamiento & purificación
10.
Sci Rep ; 8(1): 12491, 2018 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-30131501

RESUMEN

Since the invention of Computed Tomography (CT), many technological advances emerged to improve the image sensitivity and resolution. However, no new source types were developed for clinical use. In this study, for the first time, coherent monochromatic X-rays from a synchrotron radiation source were used to acquire 3D CTs on patients. The aim of this work was to evaluate the clinical potential of the images acquired using Synchrotron Radiation CT (SRCT). SRCTs were acquired using monochromatic X-rays tuned at 80 keV (0.350 × 0.350 × 2 mm3 voxel size). A quantitative image quality comparison study was carried out on phantoms between a state of the art clinical CT and SRCT images. Dedicated iterative algorithms were developed to optimize the image quality and further reduce the delivered dose by a factor of 12 while keeping a better image quality than the one obtained with a clinical CT scanner. We finally show in this paper the very first SRCT results of one patient who received Synchrotron Radiotherapy in an ongoing clinical trial. This demonstrates the potential of the technique in terms of image quality improvement at a reduced radiation dose for inner ear visualization.


Asunto(s)
Interpretación de Imagen Radiográfica Asistida por Computador/normas , Tomografía Computarizada por Rayos X/instrumentación , Algoritmos , Diseño de Equipo , Humanos , Fantasmas de Imagen , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/instrumentación , Sincrotrones
11.
Prev Vet Med ; 81(1-3): 3-20, 2007 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-17544160

RESUMEN

Risk analysis has only been regularly used in the management of aquatic animal health in recent years. The Agreement on the Application of Sanitary and Phytosanitary measures (SPS) stimulated the application of risk analysis to investigate disease risks associated with international trade (import risk analysis-IRA). A majority (9 of 17) of the risk analyses reviewed were IRA. The other major focus has been the parasite of Atlantic salmon--Gyrodactylus salaris. Six studies investigated the spread of this parasite, between countries, rivers and from farmed to wild stocks, and clearly demonstrated that risk analysis can support aquatic animal health policy development, from international trade and biosecurity to disease interaction between wild and farmed stocks. Other applications of risk analysis included the spread of vertically transmitted pathogens and disease emergence in aquaculture. The Covello-Merkhofer, risk analysis model was most commonly used and appears to be a flexible tool not only for IRA but also the investigation of disease spread in other contexts. The limitations of the identified risk assessments were discussed. A majority were qualitative, partly due to the lack of data for quantitative analysis, and this, it can be argued, constrained their usefulness for trade purposes (i.e. setting appropriate sanitary measures); in other instances, a qualitative result was found to be adequate for decision making. A lack of information about the disease hazards of the large number of fish species traded is likely to constrain quantitative analysis for a number of years. The consequence assessment element of a risk analysis was most likely to be omitted, or limited in scope and depth, rarely extending beyond examining the evidence of susceptibility of farmed and wild species to the identified hazard. The reasons for this are discussed and recommendations made to develop guidelines for a consistent, systematic and multi-disciplinary approach to consequence assessment. Risk analysis has improved decision making in aquatic animal health management by providing a transparent method for using the available scientific information. The lack of data is the main constraint to the application of risk analysis in aquatic animal health. The identification of critical parameters is an important output from risk analysis models which should be used to prioritise research.


Asunto(s)
Acuicultura/métodos , Comercio , Enfermedades de los Peces/epidemiología , Enfermedades de los Peces/transmisión , Medición de Riesgo , Gestión de Riesgos , Animales , Toma de Decisiones , Peces , Cooperación Internacional , Factores de Riesgo , Especificidad de la Especie
12.
Dev Biol (Basel) ; 129: 65-9, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18306520

RESUMEN

In Norway there is an official system (ANISTAT) for reporting notifiable diseases to the Norwegian Food Safety Authority, which is mainly done by veterinarians and laboratories. Another separate official system (HAVBRUKSDATA) is also in place, for reporting production data from fish farms, such as the number of fish put into the sea, and their weight, density, feed consumption and mortality. The reported data are aggregated monthly with information from companies' private databases related to each production site and each production unit. There also are official procedures in place for the registration of drugs used in aquaculture, based on veterinary prescriptions. However there is no electronic system for active reporting diseases influencing production and/or welfare. It is our aim to establish a more advanced official system for monitoring the health situation in Norwegian fish farms (MFISK) by linking relevant production data from the various private databases to an official disease database. The output of the new system will be improved statistics on diseases in the Norwegian fish farming industry, with diseases sorted by their impact on production and welfare. This will enable us to identify diseases that, over time, cause such losses that they should be dealt with by the authorities, or by the farmers themselves. It will also have an early warning function regarding new/emerging diseases or disease trends. This system quantifies losses due to health problems and, in the long run, will be a useful tool for strengthening fish health. The system aims to combine data from various sources: the veterinary and fisheries authorities in Norway, farmers, veterinarians and laboratories. To be sustainable, it will need the active and constructive cooperation of all these stakeholders.


Asunto(s)
Acuicultura/métodos , Notificación de Enfermedades/métodos , Animales , Bases de Datos Factuales , Programas de Gobierno/organización & administración , Programas de Gobierno/normas , Noruega
13.
Cell Death Discov ; 2: 16017, 2016 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-27275396

RESUMEN

In vertebrates, 14-3-3 proteins form a family of seven highly conserved isoforms with chaperone activity, which bind phosphorylated substrates mostly involved in regulatory and checkpoint pathways. 14-3-3 proteins are the most abundant protein in the brain and are abundantly found in the cerebrospinal fluid in neurodegenerative diseases, suggesting a critical role in neuron physiology and death. Here we show that 14-3-3eta-deficient mice displayed auditory impairment accompanied by cochlear hair cells' degeneration. We show that 14-3-3eta is highly expressed in the outer and inner hair cells, spiral ganglion neurons of cochlea and retinal ganglion cells. Screening of YWHAH, the gene encoding the 14-3-3eta isoform, in non-syndromic and syndromic deafness, revealed seven non-synonymous variants never reported before. Among them, two were predicted to be damaging in families with syndromic deafness. In vitro, variants of YWHAH induce mild mitochondrial fragmentation and severe susceptibility to apoptosis, in agreement with a reduced capacity of mutated 14-3-3eta to bind the pro-apoptotic Bad protein. This study demonstrates that YWHAH variants can have a substantial effect on 14-3-3eta function and that 14-3-3eta could be a critical factor in the survival of outer hair cells.

14.
J Mol Biol ; 303(2): 117-23, 2000 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-11023779

RESUMEN

Cel5 (formerly known as endoglucanase Z) of Erwinia chrysanthemi is secreted by the Out type II pathway. Previous studies have shown that the catalytic domain (CD), linker region (LR) and cellulose-binding domain (CBD) each contain information needed for secretion. The aim of this work was to further investigate the secretion-related information present in the CBD(Cel5). Firstly(, )deleting a surface-exposed flexible loop had no effect on secretion. This indicated that some structural freedom is tolerated by the type II system. Secondly, mutation of a single tryptophan residue, previously shown to be important for binding to cellulose, i.e. Trp43, was found also to impair secretion. This indicated that the flat cellulose-binding surface of CBD(Cel5 )contains secretion-related information. Thirdly, CBD(Cel5) was substituted by the CBD(EGG) of Alteromonas haloplanctis endoglucanase G, yielding a hybrid protein CD(Cel5)-LR(Cel5)-CBD(EGG) that exhibited 90 % identity with Cel5, including the Trp43 residue. The hybrid protein was not secreted. This indicated that the Trp43 residue is necessary but not sufficient for secretion. Here we propose a model in which the secretion of Cel5 involves a transient intramolecular interaction between the cellulose-binding surface of CBD(Cel5) and a region close to the entry into the active site in CD(Cel5). Once secreted, the protein may then open out to allow the cellulose-binding surface of CBD(Cel5 )to interact with the surface of the cellulose substrate. An implication of this model is that protein molecules fold to a specific secretion-competent conformation prior to secretion that is different from the folding state of the secreted species.


Asunto(s)
Celulasa/metabolismo , Celulosa/metabolismo , Dickeya chrysanthemi/enzimología , Mutación/genética , Señales de Clasificación de Proteína/genética , Triptófano/genética , Sustitución de Aminoácidos/genética , Sitios de Unión , Celulasa/química , Celulasa/genética , Dickeya chrysanthemi/citología , Dickeya chrysanthemi/metabolismo , Modelos Moleculares , Periplasma/enzimología , Periplasma/metabolismo , Unión Proteica , Señales de Clasificación de Proteína/fisiología , Estructura Terciaria de Proteína , Eliminación de Secuencia/genética , Triptófano/metabolismo
15.
J Mol Biol ; 287(3): 609-25, 1999 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-10092463

RESUMEN

The N-terminal cellulose-binding domains CBDN1 and CBDN2 from Cellulomonas fimi cellulase CenC each adopt a jelly-roll beta-sandwich structure with a cleft into which amorphous cellulose and soluble cellooligosaccharides bind. To determine the orientation of the sugar chain within these binding clefts, the association of TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl-4-yl) spin-labeled derivatives of cellotriose and cellotetraose with isolated CBDN1 and CBDN2 was studied using heteronuclear 1H-15N NMR spectroscopy. Quantitative binding measurements indicate that the TEMPO moiety does not significantly perturb the affinity of the cellooligo-saccharide derivatives for the CBDs. The paramagnetic enhancements of the amide 1HN longitudinal (DeltaR1) and transverse (DeltaR2) relaxation rates were measured by comparing the effects of TEMPO-cellotetraose in its nitroxide (oxidized) and hydroxylamine (reduced) forms on the two CBDs. The bound spin-label affects most significantly the relaxation rates of amides located at both ends of the sugar-binding cleft of each CBD. Similar results are observed with TEMPO-cellotriose bound to CBDN1. This demonstrates that the TEMPO-labeled cellooligosaccharides, and by inference strands of amorphous cellulose, can associate with CBDN1 and CBDN2 in either orientation across their beta-sheet binding clefts. The ratio of the association constants for binding in each of these two orientations is estimated to be within a factor of five to tenfold. This finding is consistent with the approximate symmetry of the hydrogen-bonding groups on both the cellooligosaccharides and the residues forming the binding clefts of the CenC CBDs.


Asunto(s)
Celulosa/metabolismo , Bacilos Grampositivos Asporogénicos/enzimología , Oligosacáridos/metabolismo , beta-Glucosidasa/química , beta-Glucosidasa/metabolismo , Sitios de Unión , Secuencia de Carbohidratos , Óxidos N-Cíclicos , Espectroscopía de Resonancia por Spin del Electrón , Electrones , Glucano 1,4-beta-Glucosidasa , Enlace de Hidrógeno , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Datos de Secuencia Molecular , Oligosacáridos/química , Estructura Secundaria de Proteína , Protones , Marcadores de Spin
17.
Diabetes Care ; 23(8): 1119-23, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10937508

RESUMEN

OBJECTIVE: To examine the 10-year mortality and effect of diabetes duration on overall and cause-specific mortality in diabetic subjects in the Verona Diabetes Study (VDS). RESEARCH DESIGN AND METHODS: Records from diabetes clinics, family physicians, and a drug consumption database were used to identify 5,818 subjects > or =45 years of age with type 2 diabetes who were alive and residing in Verona, Italy on 31 December 1986. Vital status of each subject was ascertained on 31 December 1996. Underlying causes of death were determined from death certificates. Death rates and death rate ratios (DRRs) were computed and standardized to the population of Verona in 1991. RESULTS: During the study, 2,328 subjects died; 974 deaths were attributable to cardiovascular disease, 517 to neoplasms, 324 to diabetes-related diseases, 134 to digestive diseases, 250 to other natural causes, and 48 to external causes. There were 81 subjects who died of unknown causes. Death rates from natural causes were higher in men than in women (DRR 1.4, 95% CI 1.2-1.5) and rose in both sexes with increasing duration of diabetes (P = 0.001). Among the natural causes of death, those for diabetes-related diseases were strongly related to diabetes duration (P = 0.001). a modest relationship with duration was also found for ischemic heart disease in men (P = 0.07). CONCLUSIONS: Cardiovascular disease was the principal cause of death among people with type 2 diabetes in the VDS. Rates for natural causes of death rose with increasing duration of diabetes. Deaths from diabetes-related diseases in both sexes and from ischemic heart disease in men were largely responsible for this increase.


Asunto(s)
Causas de Muerte , Diabetes Mellitus Tipo 2/mortalidad , Diabetes Mellitus Tipo 2/fisiopatología , Adolescente , Adulto , Factores de Edad , Anciano , Enfermedades Cardiovasculares/mortalidad , Niño , Preescolar , Estudios de Cohortes , Femenino , Humanos , Lactante , Italia , Masculino , Registros Médicos , Persona de Mediana Edad , Neoplasias/mortalidad , Factores Sexuales , Factores de Tiempo
18.
Diabetes Care ; 23(1): 45-50, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10857967

RESUMEN

OBJECTIVE: In the present study, we evaluated whether the coefficient of variation (CV) of fasting plasma glucose (FPG) over a 3-year period was a significant predictor of mortality in type 2 diabetic patients aged 56-74 years. RESEARCH DESIGN AND METHODS: All type 2 diabetic patients (n = 1,409) aged 56-74 years attending the Verona Diabetes Clinic and having at least two FPG determinations in each of the years 1984-1986 were followed for 10 years (1987-1996) to assess total and cause-specific mortality Patients were grouped into tertiles of mean and CV of FPG during 1984-1986. These parameters as well as sex, age, diabetes duration, insulin treatment, smoking, hypertension, and hypercholesterolemia were included in multivariate survival analyses. RESULTS: During the follow-up, 468 patients died. The CV of FPG was an independent predictor of total, cardiovascular, and cancer mortality. Mean FPG was a predictor of total mortality only when the CV of FPG was not included in the analyses. CONCLUSIONS: Long-term variability of fasting glucose is an independent predictor of mortality in patients with type 2 diabetes. The CV of FPG might be considered a useful additional parameter in the management of these patients.


Asunto(s)
Glucemia/análisis , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/mortalidad , Ayuno , Anciano , Análisis de Varianza , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/epidemiología , Angiopatías Diabéticas/epidemiología , Angiopatías Diabéticas/mortalidad , Femenino , Humanos , Hipercolesterolemia/epidemiología , Hipertensión/epidemiología , Italia/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Probabilidad , Fumar , Tasa de Supervivencia , Factores de Tiempo
19.
Phys Med Biol ; 60(9): 3433-40, 2015 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-25856228

RESUMEN

X-ray refraction-based computer tomography imaging is a well-established method for nondestructive investigations of various objects. In order to perform the 3D reconstruction of the index of refraction, two or more raw computed tomography phase-contrast images are usually acquired and combined to retrieve the refraction map (i.e. differential phase) signal within the sample. We suggest an approximate method to extract the refraction signal, which uses a single raw phase-contrast image. This method, here applied to analyzer-based phase-contrast imaging, is employed to retrieve the index of refraction map of a biological sample. The achieved accuracy in distinguishing the different tissues is comparable with the non-approximated approach. The suggested procedure can be used for precise refraction computer tomography with the advantage of a reduction of at least a factor of two of both the acquisition time and the dose delivered to the sample with respect to any of the other algorithms in the literature.


Asunto(s)
Algoritmos , Refractometría/métodos , Tomografía Computarizada por Rayos X/métodos , Rayos X
20.
Nanoscale ; 7(16): 7352-60, 2015 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-25825056

RESUMEN

TiO2 microparticles are widely used in food products, where they are added as a white food colouring agent. This food additive contains a significant amount of nanoscale particles; still the impact of TiO2 nanoparticles (TiO2-NPs) on gut cells is poorly documented. Our study aimed at evaluating the impact of rutile and anatase TiO2-NPs on the main functions of enterocytes, i.e. nutrient absorption driven by solute-liquid carriers (SLC transporters) and protection against other xenobiotics driven by efflux pumps from the ATP-binding cassette (ABC) family. We show that acute exposure of Caco-2 cells to both anatase (12 nm) and rutile (20 nm) TiO2-NPs induce early upregulation of a battery of efflux pumps and nutrient transporters. In addition they cause overproduction of reactive oxygen species and misbalance redox repair systems, without inducing cell mortality or DNA damage. Taken together, these data suggest that TiO2-NPs may increase the functionality of gut epithelial cells, particularly their property to form a protective barrier against exogenous toxicants and to absorb nutrients.


Asunto(s)
Nanopartículas del Metal/química , Titanio/química , Células CACO-2 , Supervivencia Celular/efectos de los fármacos , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Transportador de Glucosa de Tipo 1/metabolismo , Transportador de Glucosa de Tipo 4/metabolismo , Humanos , Intestinos/citología , Nanopartículas del Metal/toxicidad , Especies Reactivas de Oxígeno/metabolismo
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