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1.
Biol Lett ; 16(4): 20200005, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32228400

RESUMEN

Here, we use 30 long-term, high-resolution palaeoecological records from Mexico, Central and South America to address two hypotheses regarding possible drivers of resilience in tropical forests as measured in terms of recovery rates from previous disturbances. First, we hypothesize that faster recovery rates are associated with regions of higher biodiversity, as suggested by the insurance hypothesis. And second, that resilience is due to intrinsic abiotic factors that are location specific, thus regions presently displaying resilience in terms of persistence to current climatic disturbances should also show higher recovery rates in the past. To test these hypotheses, we applied a threshold approach to identify past disturbances to forests within each sequence. We then compared the recovery rates to these events with pollen richness before the event. We also compared recovery rates of each site with a measure of present resilience in the region as demonstrated by measuring global vegetation persistence to climatic perturbations using satellite imagery. Preliminary results indeed show a positive relationship between pre-disturbance taxonomic richness and faster recovery rates. However, there is less evidence to support the concept that resilience is intrinsic to a region; patterns of resilience apparent in ecosystems presently are not necessarily conservative through time.


Asunto(s)
Ecosistema , Bosques , Biodiversidad , México , América del Sur , Árboles
2.
Phys Chem Chem Phys ; 21(38): 21596-21602, 2019 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-31538993

RESUMEN

Electronic structure modifications due to strain are an effective method for tailoring nano-scale functional materials. Demonstrated on nickel oxide (NiO) thin films, Resonant Inelastic X-ray Scattering (RIXS) at the transition-metal M2,3-edge is shown to be a powerful tool for measuring the electronic structure modification due to strain in the near-surface region. Analyses from the M2,3-edge RIXS in comparison with dedicated crystal field multiplet calculations show distortions in 40 nm NiO grown on a magnesium oxide (MgO) substrate (NiO/MgO) similar to those caused by surface relaxation of bulk NiO. The films of 20 and 10 nm NiO/MgO show slightly larger differences from bulk NiO. Quantitatively, the NiO/MgO samples all are distorted from perfect octahedral (Oh) symmetry with a tetragonal parameter Ds of about -0.1 eV, very close to the Ds distortion from octahedral (Oh) symmetry parameter of -0.11 eV obtained for the surface-near region from a bulk NiO crystal. Comparing the spectra of a 20 nm film of NiO grown on a 20 nm magnetite (Fe3O4) film on a MgO substrate (NiO/Fe3O4/MgO) with the calculated multiplet analyses, the distortion parameter Ds appears to be closer to zero, showing that the surface-near region of this templated film is less distorted from Oh symmetry than the surface-near region in bulk NiO. Finally, the potential of M2,3-edge RIXS for other investigations of strain on electronic structure is discussed.

3.
Phys Rev Lett ; 116(25): 257202, 2016 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-27391747

RESUMEN

Using femtosecond time-resolved resonant magnetic x-ray diffraction at the Ho L_{3} absorption edge, we investigate the demagnetization dynamics in antiferromagnetically ordered metallic Ho after femtosecond optical excitation. Tuning the x-ray energy to the electric dipole (E1, 2p→5d) or quadrupole (E2, 2p→4f) transition allows us to selectively and independently study the spin dynamics of the itinerant 5d and localized 4f electronic subsystems via the suppression of the magnetic (2 1 3-τ) satellite peak. We find demagnetization time scales very similar to ferromagnetic 4f systems, suggesting that the loss of magnetic order occurs via a similar spin-flip process in both cases. The simultaneous demagnetization of both subsystems demonstrates strong intra-atomic 4f-5d exchange coupling. In addition, an ultrafast lattice contraction due to the release of magneto-striction leads to a transient shift of the magnetic satellite peak.

4.
Rev Sci Tech ; 35(2): 435-444, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27917981

RESUMEN

Pastoralism is rarely viewed as a major future form of land use, because of well-documented cases of rangeland degradation, attributed to irrational overstocking by pastoralists, and the subsequent losses of ecosystem services. However, pastoralists were actually encouraged to settle and adopt such strategies, copied from rangelands with higher and more reliable rainfall. This curtailed mobility resulted in a shift from opportunistic and extensive land use to more intensive and settled forms of use. The purpose of this review is to examine the link between pastoralism and the provision of ecosystem services by rangelands, focusing on biodiversity conservation and carbon sequestration. Pastoralists employ several techniques to manage rangeland resources, including mobility, herding, corralling, grazing reserves and the use of fire. With these strategies, pastoralists have contributed to the enhancement of rangeland biodiversity and the long-term conservation of important wildlife habitats. Pastoralists also possess detailed knowledge of rangeland plants and their uses, which could be valuable in the assessment, conservation and utilisation of rangeland biodiversity. Similarly, traditional pastoral rangeland management practices, such as the use of seasonal grassland reserves and livestock mobility, influence vegetation composition, coverage and abundance in rangelands and offer tools for biomass and soil carbon restoration, contributing to the mitigation of climate change. However, various internal and external factors have curtailed traditional management practices and livestock mobility, breaking the co-evolved balance of vegetation, wildlife and land use, thus exposing rangeland to continued livestock pressure, which often leads to degradation. Rather than abandoning pastoralism, the revitalisation of traditional practices and indigenous knowledge is vital to secure sustainable livelihoods for millions of pastoralists and to maintain rangeland biodiversity and ecosystem services.


Parmi les modalités d'utilisation des terres, le pastoralisme n'est guère considéré comme présentant un fort potentiel d'avenir, en raison d'exemples bien documentés de prairies dégradées suite à leur surexploitation irrationnelle par les pasteurs, entraînant une baisse des services écosystémiques qui leur étaient associés. Il faut toutefois rappeler que ces mêmes pasteurs avaient d'abord été encouragés à se sédentariser et à adopter ce type de stratégies, directement inspirées des pratiques d'élevage appliquées dans les prairies bénéficiant de précipitations plus importantes et plus fiables. Le déclin de la mobilité s'est traduit par le passage d'une utilisation opportuniste et extensive des terres à des formes d'exploitation plus intensives et sédentarisées. Les auteurs se sont attachés à faire apparaître les liens entre le pastoralisme et les services écosystémiques rendus par les prairies, en premier lieu la protection de la biodiversité et la séquestration de carbone. Les pasteurs recourent à diverses techniques pour gérer les ressources des prairies, dont la transhumance, la conduite des troupeaux, l'érection de clôtures, la rotation des pâtures et l'usage du feu. En déployant ces stratégies, les pasteurs ont contribué à améliorer la biodiversité des prairies et à assurer la conservation durable d'habitats importants pour la faune sauvage. Les pasteurs possèdent également une connaissance détaillée des espèces végétales poussant dans les prairies et de leur utilisation, qui s'avère précieuse pour évaluer, conserver et utiliser la biodiversité des prairies. De même, les pratiques pastorales traditionnelles de gestion des prairies telles que la rotation saisonnière des parcelles et les déplacements des troupeaux influent sur la répartition, la couverture et l'abondance de la végétation des prairies et constituent des outils permettant de réparer la biomasse et de séquestrer le carbone des sols, contribuant ainsi à atténuer le réchauffement climatique. Néanmoins, plusieurs facteurs internes et externes ont limité les pratiques de gestion traditionnelles et la mobilité des troupeaux, brisant l'équilibre d'une coévolution parallèle de la végétation, la faune sauvage et l'exploitation des terres, et exposant de ce fait les prairies à une pression permanente, souvent suivie de leur dégradation. Plutôt que de renoncer au pastoralisme, il est désormais crucial de revitaliser les pratiques traditionnelles et les savoirs autochtones afin de sécuriser les moyens de subsistance de millions de pasteurs et de préserver la biodiversité des prairies et les services écosystémiques.


Al pensar en las principales modalidades de usos del suelo de cara al futuro, rara vez se tiene en cuenta el pastoreo. Ello se debe a la existencia de casos probados de degradación de los pastos, atribuida a un acopio excesivo e irracional por parte de los pastores, y a la consiguiente pérdida de servicios ecosistémicos. La realidad, sin embargo, es que las comunidades de pastores fueron alentadas a asentarse y adoptar tales procederes, importados de zonas de pastizales con niveles más elevados y constantes de pluviosidad. La consiguiente limitación de la movilidad llevó a pasar de un uso oportunista y extensivo de las tierras a modalidades de explotación más intensivas y sedentarias. Los autores examinan aquí el vínculo entre el pastoreo y los servicios ecosistémicos ligados a los pastizales, centrándose sobre todo en la conservación de la diversidad biológica y el secuestro de carbono. Las sociedades de pastores emplean varias técnicas para gestionar los recursos que suponen las tierras de pasto, en particular la movilidad, el uso de rebaños, corrales y reservas de pastizales y el recurso al fuego. Con estas estrategias los pastores han contribuido a mejorar la diversidad biológica de los pastizales y a conservar duraderamente importantes hábitats de la fauna salvaje. Estas sociedades atesoran asimismo un detallado conocimiento de las plantas que forman los pastizales y de sus usos, lo que puede revestir gran utilidad para evaluar, preservar y utilizar la biodiversidad de los pastizales. Análogamente, las prácticas tradicionales de gestión de pastos que aplican los pastores (como el uso de reservas estacionales de tierras de pasto o la movilidad del ganado) influyen en la composición vegetal, la cobertura y la abundancia de los pastizales y brindan así herramientas para restaurar la biomasa y el carbono del suelo, ayudando con ello a mitigar el cambio climático. Sin embargo, hay una serie de factores internos y externos que han coartado las prácticas de gestión tradicionales y la movilidad del ganado, alterando el equilibrio entre vegetación, fauna salvaje y usos del suelo que se había alcanzado por coevolución y sometiendo así a los pastizales a una presión ganadera continua, que a menudo acaba por degradarlos. Más que de abandonar el pastoreo, se trata pues de revitalizar las prácticas tradicionales y el saber indígena como expediente crucial para procurar medios de sustento duraderos a los millones de personas que viven del pastoreo y a la vez mantener la diversidad biológica y los servicios ecosistémicos de los pastizales.


Asunto(s)
Crianza de Animales Domésticos/métodos , Biodiversidad , Secuestro de Carbono , Conservación de los Recursos Naturales , Ecosistema , Animales , Humanos , Ganado , Poaceae
5.
Schweiz Arch Tierheilkd ; 157(10): 559-62, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26897771

RESUMEN

A 3-year-old cat was presented with anorexia and vomiting. Palpation revealed a caudal abdominal mass. Ultrasound and explorative abdominal surgery revealed a cystic mass in the jejunum. Histopathologic findings were consistent with an epidermoid cyst. The cyst was likely of congenital origin, since the cat had not undergone previous abdominal surgery, and gradually grew to reach a size that caused intestinal obstruction. Extrapolating from findings in people, intestinal epidermoid cysts are considered benign with a good long-term prognosis when completely excised.


Asunto(s)
Enfermedades de los Gatos/diagnóstico , Enfermedades de los Gatos/cirugía , Quiste Epidérmico/veterinaria , Obstrucción Intestinal/veterinaria , Enfermedades del Yeyuno/veterinaria , Animales , Gatos , Quiste Epidérmico/diagnóstico , Quiste Epidérmico/cirugía , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Enfermedades del Yeyuno/diagnóstico , Enfermedades del Yeyuno/cirugía , Masculino
6.
Gene Ther ; 21(7): 682-93, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24807806

RESUMEN

Intrastriatal injection of recombinant adeno-associated viral vector serotype 2/1 (rAAV2/1) to overexpress the neurotrophic factor pleiotrophin (PTN) provides neuroprotection for tyrosine hydroxylase immunoreactive (THir) neurons in the substantia nigra pars compacta (SNpc), increases THir neurite density in the striatum (ST) and reverses functional deficits in forepaw use following 6-hydroxydopamine (6-OHDA) toxic insult. Glial cell line-derived neurotrophic factor (GDNF) gene transfer studies suggest that optimal neuroprotection is dependent on the site of nigrostriatal overexpression. The present study was conducted to determine whether enhanced neuroprotection could be accomplished via simultaneous rAAV2/1 PTN injections into the ST and SN compared with ST injections alone. Rats were unilaterally injected in the ST alone or injected in both the ST and SN with rAAV2/1 expressing either PTN or control vector. Four weeks later, all rats received intrastriatal injections of 6-OHDA. Rats were euthanized 6 or 16 weeks relative to 6-OHDA injection. A novel selective total enumeration method to estimate nigral THir neuron survival was validated to maintain the accuracy of stereological assessment. Long-term nigrostriatal neuroprotection and functional benefits were only observed in rats in which rAAV2/1 PTN was injected into the ST alone. Results suggest that superior preservation of the nigrostriatal system is provided by PTN overexpression delivered to the ST and restricted to the ST and SN pars reticulata and is not improved with overexpression of PTN within SNpc neurons.


Asunto(s)
Proteínas Portadoras/metabolismo , Cuerpo Estriado/metabolismo , Citocinas/metabolismo , Enfermedades Neurodegenerativas/terapia , Fármacos Neuroprotectores/metabolismo , Sustancia Negra/metabolismo , Animales , Proteínas Portadoras/genética , Línea Celular , Citocinas/genética , Dependovirus/genética , Modelos Animales de Enfermedad , Terapia Genética , Vectores Genéticos/administración & dosificación , Masculino , Enfermedades Neurodegenerativas/inducido químicamente , Fármacos Neuroprotectores/farmacología , Oxidopamina , Ratas , Ratas Sprague-Dawley , Transducción Genética
7.
Waste Manag ; 174: 290-299, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38071869

RESUMEN

Improving the sortability of plastic packaging film waste (PPFW) is crucial for increasing the recycling rate in Austria as they account for 150,000 t of the annually produced 300,000 t of plastic packaging waste. Currently PPFW is thermally recovered, as it is impossible to separate the mechanically recyclable monomaterial films from the non mechanically-recyclable multimaterial films. In this study, machine learning models capable of classifying inline into monolayer and multilayer films of PPFW according to their spectral fingerprint taken in transflection were created. Feature selection methods, like PCA and MRMR F-Tests, identified the most relevant spectral ranges for classification, that show the least redundancy and highest relevance. This effective subset of features decreases the required complexity of the model while reducing prediction time without compromising accuracy. The resulting models achieved a prediction accuracy of 85 % on unseen specimens with minimal prediction latency, effectively showing the inline applicability of these models in sorting aggregates.


Asunto(s)
Polímeros , Administración de Residuos , Plásticos , Reciclaje , Austria
8.
Artículo en Inglés | MEDLINE | ID: mdl-38619791

RESUMEN

PURPOSE: Heart valve disease is commonly treated by minimally invasive procedures with guide wires and catheterization. The main purpose of this study is to find out whether an extension of the guide wire with a sensor can support the surgeon within the blood vessel to reduce X-ray necessity. METHODS: A smart guide wire is developed by an extension with a flex-bending sensor to evaluate the sensor signal with and without "blood" flow at a constant compression force. Various surgically relevant investigations are performed. For assessment, the mean temporal average of the moving averaged filtered ADC signal and a subsequent FFT are carried out. RESULTS: Results show that there is a smaller sensor signal when the applied force or bending at the sensor is higher. In all investigations, there was a different sensor signal. The flex-bending sensor can detect the effect of pulsatile flow. The smallest temporal averaged signal difference between reference and clamp in the front wire's tip is 1.09%. For example, the mean temporal average of the filtered ADC signal for different clinically relevant scenarios is between 2550 and 2900. CONCLUSIONS: The results show that the sensorized guide wire developed for catheterization can support aortic valve implementation. The sensor sensitivity is sufficient to detect even very small variations within the blood vessel and therefore is promising to support catheterization heart valve surgeries in future.

9.
Diabetologia ; 56(1): 126-35, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23052055

RESUMEN

AIMS/HYPOTHESIS: IL-12 is an important cytokine in early inflammatory responses and is implicated in the immune-mediated pathogenesis of pancreatic islets in diabetes. However, little is known about the direct effects of IL-12 on islets and beta cells. METHODS: In this study, beta cell function, gene expression and protein production were assessed in primary human donor islets and murine beta cell lines in response to stimulation with IL-12 or a pro-inflammatory cytokine cocktail (TNF-α, IL-1ß and IFN-γ). RESULTS: The pro-inflammatory cytokine cocktail induced islet dysfunction and potently increased the expression and production of IL-12 ligand and IL-12 receptor in human islets. In human islets, the receptor for IL-12 co-localised to the cell surface of insulin-producing cells. Both IL-12 ligand and IL-12 receptor are expressed in the homogeneous beta cell line INS-1. IL-12 induced changes in gene expression, including a dose-dependent upregulation of IFNγ (also known as IFNG), in INS-1 cells. A neutralising antibody to IL-12 directly inhibited IFNγ gene expression in human donor islets induced by either IL-12 or pro-inflammatory cytokine stimulation. Functionally, IL-12 impaired glucose-stimulated insulin secretion (GSIS) in INS-1 cells and human donor islets. A neutralising antibody to IL-12 reversed the beta cell dysfunction (uncoupling of GSIS or induction of caspase-3 activity) induced by pro-inflammatory cytokines. CONCLUSIONS/INTERPRETATION: These data identify beta cells as a local source of IL-12 ligand and suggest a direct role of IL-12 in mediating beta cell pathology.


Asunto(s)
Diabetes Mellitus Tipo 2/metabolismo , Regulación de la Expresión Génica , Células Secretoras de Insulina/metabolismo , Interleucina-12/biosíntesis , Islotes Pancreáticos/metabolismo , Receptores de Interleucina-12/metabolismo , Transducción de Señal , Animales , Anticuerpos Neutralizantes/metabolismo , Línea Celular , Membrana Celular/metabolismo , Citocinas/metabolismo , Diabetes Mellitus Tipo 2/inmunología , Humanos , Insulina/metabolismo , Secreción de Insulina , Células Secretoras de Insulina/inmunología , Interferón gamma/metabolismo , Interleucina-12/antagonistas & inhibidores , Interleucina-12/metabolismo , Islotes Pancreáticos/inmunología , Ratones , ARN Mensajero/metabolismo , Propiedades de Superficie , Técnicas de Cultivo de Tejidos , Donantes de Tejidos
10.
Clin Genet ; 75(1): 43-9, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19021640

RESUMEN

The associations between characteristics of family relationships and family trends in cancer worry and the psychological adjustment of recipients of genetic testing for cancer susceptibility were investigated. Data provided by 178 individuals from 24 families with Lynch syndrome who participated in a cohort study investigating psychological and behavioral outcomes of genetic testing were used. Responses from multiple family members were aggregated to construct family trends representing norms and departure from norms in cancer worry. Lower perceived family cohesion at baseline and decrease in this variable at 6 months after receipt of test results were associated with higher depression scores at 12 months. More variability in cancer worry among family members at baseline was also associated with higher depression scores at 12 months. Increase in family conflict was associated with decrease in depression scores among individuals from families with higher levels of cancer worry on average and less variability among the members. Family relationships and family trends in levels of cancer worry may play important roles in the psychological adjustment of genetic test recipients. The findings highlight the complexity of familial environment surrounding individuals that undergo genetic testing and suggest the benefits of considering these factors when providing genetic services.


Asunto(s)
Depresión/psicología , Relaciones Familiares , Predisposición Genética a la Enfermedad/psicología , Pruebas Genéticas/psicología , Neoplasias/genética , Neoplasias/psicología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/psicología , Depresión/clasificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/diagnóstico , Adulto Joven
11.
Mol Cell Biol ; 7(10): 3705-12, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2824995

RESUMEN

Mouse Ltk- cells were stably transfected with cloned genes encoding the mouse major urinary proteins (MUPs). C57BL/6J MUP genomic clones encoding MUP 2 (BL6-25 and BL6-51), MUP 3 (BL6-11 and BL6-3), and MUP 4 (BL6-42) have been identified. In C57BL/6J mice, MUP 2 and MUP 4 are known to be synthesized in male, but not female, liver, and MUP 3 is known to be synthesized in both male and female liver and mammary gland. A BALB/c genomic clone (BJ-31) was shown to encode a MUP that is slightly more basic than MUP 2 and was previously shown to be synthesized in both male and female liver of BALB/c but not C57BL/6 mice. Comigration on two-dimensional polyacrylamide gels of the MUPs encoded by the transfecting gene provides a basis for tentative identification of the tissue specificity and mode of regulation of each gene. DNA sequence analysis of the 5' flanking region indicates that the different MUP genes are highly homologous (0.20 to 2.40% divergence) within the 879 base pairs analyzed. The most prominent differences in sequence occur within an A-rich region just 5' of the TATA box. This region (from -47 to -93) contains primarily A or C(A)N nucleotides and varies from 15 to 46 nucleotides in length in the different clones.


Asunto(s)
Genes , Ratones Endogámicos/genética , Proteínas/genética , Animales , Secuencia de Bases , Clonación Molecular , Enzimas de Restricción del ADN , Regulación de la Expresión Génica , Células L , Ratones , Datos de Secuencia Molecular , Transfección
12.
Schweiz Arch Tierheilkd ; 149(3): 123-7, 2007 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-17410970

RESUMEN

A 2-years old male Labrador retriever dog was presented with intermittent therapy-resistant diarrhoea, accompanied by vomiting, inappetence, apathy, and mild fever. The blood analysis showed an anaemia, neutrophilia, eosinophilia, and increased liver enzymes. Abdominal palpation was slightly painful. X-rays and echography revealed a severely enlarged liver with multiple cavernous structures. Histopathologic examination of liver biopsies showed a severe chronic granulomatous hepatitis with numerous parasitic cysts. Morphology of the cysts was compatible with the metacestode stage of Echinococcus multilocularis. The dog was only 2-years old at the time of diagnosis. Although alveolar hydatid disease of the liver is rare in dogs, it should be envisaged as a possible differential diagnosis in cases of space-occupying processes in the liver, even in young animals, as the incubation period of this disease in the dog can be considerably shorter than in humans.


Asunto(s)
Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/parasitología , Equinococosis/veterinaria , Echinococcus multilocularis/patogenicidad , Animales , Enfermedades de los Perros/patología , Perros , Equinococosis/diagnóstico , Equinococosis/patología , Echinococcus multilocularis/aislamiento & purificación , Resultado Fatal , Interacciones Huésped-Parásitos , Hígado/diagnóstico por imagen , Hígado/parasitología , Hígado/patología , Masculino , Radiografía , Ultrasonografía
15.
J Endocrinol ; 85(1): 145-9, 1980 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6930445

RESUMEN

Luteolysis was induced in rats during late pregnancy by fetoplacental removal, and was monitored by the increased activity of luteal 20 alpha-hydroxysteroid dehydrogenase (20 alpha-OHSDH). The extent of enzyme induction over a given length of time varied according to the time of day at which the fetuses and placentae were removed, 11.00 and 21.00 h appearing to give optimal and minimal enzyme activities respectively. The 20 alpha-OHSDH was more readily induced on day 19 than on day 18.


Asunto(s)
20-Hidroxiesteroide Deshidrogenasas/biosíntesis , Ritmo Circadiano , Cuerpo Lúteo/enzimología , Luteólisis , Preñez , Aborto Inducido , Animales , Inducción Enzimática , Femenino , Embarazo , Ratas
16.
Blood Coagul Fibrinolysis ; 6(8): 761-4, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8825228

RESUMEN

Activated protein C resistance (APCR), usually due to the Arg506-->Gln point mutation of the factor V gene, has emerged as the most important hereditary cause of venous thromboembolism. Using an aPTT based method in the presence of APC, together with a DNA technique based on the polymerase chain reaction, we investigated 65 leukaemic children and 65 age-matched healthy controls for the presence of this mutation. In both groups three children showed APCR. All six children showed the common factor V gene mutation, Arg506-->Gln. Although no child in the control group presented with thrombosis, all three children with acute lymphoblastic leukaemia had thromboembolic events. Whether the poor anticoagulant response to activated protein C in leukaemic children treated with prednisone, vincristine, daunorubicin and asparaginase affects the risk of thrombotic events requires a more extensive multicentre study.


Asunto(s)
Leucemia-Linfoma Linfoblástico de Células Precursoras/fisiopatología , Proteína C/metabolismo , Adolescente , Antitrombina III/metabolismo , Niño , Preescolar , Factor V/metabolismo , Femenino , Humanos , Lactante , Masculino , Estudios Prospectivos , Proteína S/metabolismo
17.
Praxis (Bern 1994) ; 100(3): 151-8, 2011 Feb 02.
Artículo en Alemán | MEDLINE | ID: mdl-21290372

RESUMEN

Health care workers are at increased risk of exposure to contaminated infectious body fluids. Guidelines exist regarding prevention of exposure and measures to take if an exposure has occurred. The goal is to evaluate the potential risk for infections with HIV, HCV and HBV rapidly, and, if necessary, to initiate an early treatment. Morbidity and the related costs may thus be lowered. The practical application of such guidelines is not always simple and will be discussed in our article.


Asunto(s)
Adhesión a Directriz , Infecciones por VIH/prevención & control , Personal de Salud , Hepatitis B/prevención & control , Hepatitis C/prevención & control , Transmisión de Enfermedad Infecciosa de Paciente a Profesional/prevención & control , Lesiones por Pinchazo de Aguja/complicaciones , Algoritmos , Estudios de Seguimiento , Infecciones por VIH/transmisión , Hepatitis B/transmisión , Hepatitis C/transmisión , Humanos , Riesgo , Factores de Riesgo , Suiza
18.
J Plant Physiol ; 168(14): 1659-66, 2011 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-21453983

RESUMEN

A common molecular regulatory pathway that involves PHYA, PHYB and floral integrator genes CONSTANS (CO), FLOWERING LOCUS T (FT) and SUPRESSOR OF OVEREXPRESSION OF CO1 (SOC1) has been suggested to participate in the regulation of photoperiod dependent processes such as flowering and dormancy. In grapevines (Vitis vinifera L.), decreasing photoperiod and low temperatures trigger the transition of buds into endodormancy (ED), a process that is accompanied by drastic changes in gene expression of VvPHYA and B in leaves. To analyse the relationship of VvPHYA, VvPHYB, and grape homologues of Arabidopsis floral integrator genes VvCO, VvFT, VvMADS8, with ED, a comparative expression analysis of these genes was performed in grapevine-leaves and buds before, during and after the transition of buds into ED. The expression of all the above genes in the bud-tissue, and the fact that photoperiod regulates differently the expression of VvPHYA and B in buds than in leaves, suggests that the bud might be an autonomous or semi-autonomous organ in perceiving and transducing the photoperiod signal. On the other hand, the coordinated down-regulation of VvFT in leaves and buds during the transition of buds into ED, and its subsequent up-regulation following the application of dormancy-breaking compounds, hydrogen cyanamide (HC) and sodium azide, suggests that VvFT could play a key role in stimulating bud-growth by repressing their entry into ED.


Asunto(s)
Cianamida/farmacología , Flores/crecimiento & desarrollo , Fitocromo/genética , Proteínas de Plantas/genética , Azida Sódica/farmacología , Vitis/genética , Frío , Regulación hacia Abajo/genética , Flores/genética , Flores/fisiología , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genes de Plantas/genética , Especificidad de Órganos , Fotoperiodo , Fitocromo/metabolismo , Hojas de la Planta/genética , Proteínas de Plantas/metabolismo , Regiones Promotoras Genéticas , ARN de Planta/genética , Transducción de Señal , Regulación hacia Arriba/genética , Vitis/crecimiento & desarrollo , Vitis/fisiología
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