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2.
Sci Total Environ ; 855: 158858, 2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36122721

RESUMEN

Climate change and land-use changes are the main drivers altering fire regimes and leading to the occurrence of megafires. Current management policies mainly focus on short-term restoration without considering how climate change might affect regeneration dynamics. We aimed to test the usefulness of ecological niche models (ENMs) to integrate the effects of climate change on tree species distributions into post-fire restoration planning. We also examined different important conceptual and methodological aspects during this novel process. We constructed ENM at fine spatial resolution (25 m) for the four main tree species (Pinus pinaster, Quercus pyrenaica, Q. faginea and Q. ilex) in an area affected by a megafire in Central Spain at two scales (local and regional), two periods (2 and 14 years after the fire) at the local scale, and under two future climate change scenarios. The usefulness of ENMs as support tools in decision-making for post-fire management was confirmed for the first time. As hypothesized, models developed at both scales are different, since they represent different scale dependent drivers of species distribution patterns. However, both provide objective information to be considered by stakeholders in combination with other sources of information. Local models generated with vegetation data 14 years after the fire provided valuable information about local and current vegetation dynamics (i.e., current microecology spatial niche prediction). Regional models are capable of considering a higher proportion of the climatic niche of species to generate reliable climate change forecasts (i.e., future macroclimate spatial niche forecast). The use of precise ENMs provide both an objective interpretation of potential habitat conditions and the opportunity of examining vegetation patches, that can be very valuable in managing restoration of areas affected by megafires under climate change conditions.


Asunto(s)
Cambio Climático , Incendios , Árboles , Ecosistema , Modelos Teóricos
4.
Medicine (Baltimore) ; 97(46): e13136, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30431582

RESUMEN

BACKGROUND: The diagnostic accuracy of the Gaxilose test (GT) for hypolactasia diagnosis has already been proved. The objectives of this clinical trial were to demonstrate the noninferiority of the GT compared to the hydrogen breath test (HBT) on the impact on diagnostic thinking and patient management, to evaluate the GT reproducibility with urine accumulated from 0 to 4 hours and from 0 to 5 hours and to assess test safety. METHODS: We conducted a randomized, parallel, noninferiority clinical trial. Patients with clinical symptoms suggestive of lactose intolerance were screened for inclusion and randomly assigned to the GT arm or the HBT arm of the study. The impact on diagnostic thinking and patient management was analyzed with pretest and posttest questionnaires in which the investigators indicated their estimated probability of hypolactasia diagnosis and the intended management before and after the GT or the HBT (noninferiority margin: -10%). The primary outcome of the study was the impact on diagnostic thinking, expressed as the mean of the absolute values of the differences between the pretest and posttest probabilities of hypolactasia diagnosis. Patients randomized to the GT arm performed also the retest to evaluate the reproducibility of the GT. RESULTS: A total of 147 patients were included in the intend-to-treat (ITT) population. Among them, 74 performed the HBT and 73 performed the GT. The results proved the noninferiority of the GT compared to the HBT on the impact on diagnostic thinking (ImpactGT = 31.74 ±â€Š23.30%; ImpactHBT = 24.28 ±â€Š19.87%; ΔGT-HBT = 7.46%; 95% confidence interval of ΔGT-HBT: 1.55%, infinite) and on patient management. The test-retest reproducibility was better for the GT with urine accumulated from 0 to 5 h: the intraclass correlation coefficient (ICC) was 0.5761, and the Kappa coefficient was 0.7548, indicative of substantial agreement between both tests. No serious adverse events were reported during the study. CONCLUSIONS: The GT has an impact on diagnostic thinking and patient management noninferior to that of the HBT, is reproducible and well tolerated. These results prove the clinical benefit of its use in the clinical practice (ClinicalTrials.gov identifier: NCT02636413).


Asunto(s)
Pruebas Respiratorias/métodos , Disacáridos/metabolismo , Intolerancia a la Lactosa/diagnóstico , Xilosa/orina , Adulto , Anciano , Toma de Decisiones , Disacáridos/administración & dosificación , Disacáridos/efectos adversos , Femenino , Humanos , Hidrógeno/metabolismo , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados
5.
Front Plant Sci ; 9: 825, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30013581

RESUMEN

In the Mediterranean region, wildfires are a major disturbance, determined by ecosystem and forest species characteristics. Both the flammability and resistance to fire of a mixed forest may vary from those of the individual species. Two mixed Mediterranean woodlands, a Cupressus sempervirens and Quercus ilex stand in Italy; and a Juniperus thurifera and Quercus faginea stand in Spain were investigated. Laboratory flammability tests were conducted on live foliage, litter samples and on litter beds from individual and mixed species to evaluate: (i) the flammability traits of the mixtures of live foliage and litter samples; (ii) whether the flammability of the two-species mixtures are non-additive, i.e., differ from expected flammability based on arithmetic sum of the single effects of each components species in monospecific fuel; (iii) the ignition success and initial fire propagation in litter beds. Flammability tests were also conducted on bark samples to estimate the resistance of the tree species to fire. The ignitibility of live foliage was lower and the combustibility was higher in Cupressaceae than in Quercus. Non-additive effects were observed in some flammability components of live foliage and litter, especially in the mixtures of C. sempervirens and Q. ilex. Ignitability and combustibility were higher and lower than expected, respectively, and tended to be driven by Quercus), while the consumability was lowered more than expected by both Cupressaceae. The ignition success in the litter beds was low, especially for the presence of Cupressaceae that increase the bulk density of the mixtures. Cupressaceae, which have a thinner bark, suffered more damage to the cambium after shorter exposure to the heat source than Quercus species. In all the species studied, time to reach lethal temperatures in the cambium was dependent on thickness rather than on flammability of the bark. The study findings revealed that tree species may influence flammability of mixed fuels disproportionately to their load. The studied species showed to exert a contrasted effect on flammability of the mixtures, increasing ignitability and decreasing combustibility and consumability well out of their proportion in the mixture. This may potentially influence fire dynamics in mixed forests.

6.
Biomed Res Int ; 2017: 8421418, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29147660

RESUMEN

Hypolactasia, or intestinal lactase deficiency, affects more than half of the world population. Currently, xylose quantification in urine after gaxilose oral administration for the noninvasive diagnosis of hypolactasia is performed with the hand-operated nonautomatable phloroglucinol reaction. This work demonstrates that a new enzymatic xylose quantification method, based on the activity of xylose dehydrogenase from Caulobacter crescentus, represents an excellent alternative to the manual phloroglucinol reaction. The new method is automatable and facilitates the use of the gaxilose test for hypolactasia diagnosis in the clinical practice. The analytical validation of the new technique was performed in three different autoanalyzers, using buffer or urine samples spiked with different xylose concentrations. For the comparison between the phloroglucinol and the enzymatic assays, 224 urine samples of patients to whom the gaxilose test had been prescribed were assayed by both methods. A mean bias of -16.08 mg of xylose was observed when comparing the results obtained by both techniques. After adjusting the cut-off of the enzymatic method to 19.18 mg of xylose, the Kappa coefficient was found to be 0.9531, indicating an excellent level of agreement between both analytical procedures. This new assay represents the first automatable enzymatic technique validated for xylose quantification in urine.


Asunto(s)
Proteínas Bacterianas/química , Deshidrogenasas de Carbohidratos/química , Caulobacter crescentus/enzimología , Intolerancia a la Lactosa/orina , Xilosa/orina , Femenino , Humanos , Masculino
7.
Environ Manage ; 52(2): 467-80, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23765042

RESUMEN

Assessment of the flammability of ornamental vegetation (particularly hedges) planted around houses is necessary in light of the increasing urbanization of the wildland-urban interfaces (WUIs) and the high fire occurrence in such areas. The structure and flammability of seven of the species most frequently planted as hedges in Provence (southeastern France) were studied at particle level. Spatial repartition of the different types of fuel particles within plants was assessed by means of the cube method. The leaf flammability was assessed using an epiradiator as a burning device, and measurements of foliar physical characteristics and gross heat of combustion (GHC) helped to explain the results of burning experiments. Co-inertia analysis revealed that species with thin leaves were quick to ignite (Pyracantha coccinea, Phyllostachys sp.) and species with high leaf GHC burned the longest (Pittosporum tobira, Nerium oleander). Species presenting high ignitability (Photinia fraseri, Phyllostachys sp. and Pyracantha coccinea) were characterized by high foliar surface area-to-volume ratio, and species presenting lower ignitability were characterized by high GHC (Pittosporum tobira, Nerium oleander, Cupressus sempervirens). Hierarchical cluster analysis of the flammability variables (ignition frequency, time-to-ignition and flaming duration) categorized the relative flammability of the seven species (including dead Cupressus sempervirens) in five clusters of species from poorly flammable (Pittosporum tobira) to extremely flammable (dead Cupressus sempervirens).This study provides useful information for reducing fire risk in WUIs in the study area.


Asunto(s)
Cupressus , Incendios , Magnoliopsida , Ciudades , Francia , Tamaño de la Partícula , Hojas de la Planta , Medición de Riesgo , Urbanización
10.
J Environ Manage ; 92(3): 1003-11, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21112688

RESUMEN

Prescribed burning is commonly used to prevent accumulation of biomass in fire-prone shrubland in NW Spain. However, there is a lack of knowledge about the efficacy of the technique in reducing fire hazard in these ecosystems. Fire hazard in burned shrubland areas will depend on the initial capacity of woody vegetation to recover and on the fine ground fuels existing after fire. To explore the effect that time since burning has on fire hazard, experimental tests were performed with two fuel complexes (fine ground fuels and regenerated shrubs) resulting from previous prescribed burnings conducted in a gorse shrubland (Ulex europaeus L.) one, three and five years earlier. A point-ignition source was used in burning experiments to assess ignition and initial propagation success separately for each fuel complex. The effect of wind speed was also studied for shrub fuels, and several flammability parameters were measured. Results showed that both ignition and initial propagation success of fine ground fuels mainly depended on fuel depth and were independent of time since burning, although flammability parameters indicated higher fire hazard three years after burning. In contrast, time since burning increased ignition and initial propagation success of regenerated shrub fuels, as well as the flammability parameters assessed, but wind speed had no significant effect. The combination of results of fire hazard for fine ground fuels and regenerated shrubs according to the variation in relative coverage of each fuel type after prescribed burning enabled an assessment of integrated fire hazard in treated areas. The present results suggest that prescribed burning is a very effective technique to reduce fire hazard in the study area, but that fire hazard will be significantly increased by the third year after burning. These results are valuable for fire prevention and fuel management planning in gorse shrubland areas.


Asunto(s)
Incendios , Plantas , Europa (Continente)
11.
Endocrinol Nutr ; 57(2): 71-81, 2010 Feb.
Artículo en Español | MEDLINE | ID: mdl-20227355

RESUMEN

Clinically nonfunctioning adenomas are the most frequent pituitary macroadenomas in adults. These tumors are characterized by the absence of detectable hormonal hypersecretion and are diagnosed when compression symptoms or hormonal deficiencies occur. The treatment of choice of macroadenomas is surgery, but tumoral resection is often incomplete or the patient develops tumoral recurrence. Medical therapy has been shown to produce modest tumoral reduction in some patients. Postoperative irradiation should be considered in patients with large tumoral remnants or enlargement of remnants during follow-up. Stereotactic radiotherapy has been developed to diminish the long-term complications of radiotherapy. Microadenomas tend to remain small and surveillance alone is recommended. The present article reviews the results of medical, surgical and radiation treatments.


Asunto(s)
Adenoma/terapia , Neoplasias Hipofisarias/terapia , Adenoma/tratamiento farmacológico , Adenoma/radioterapia , Adenoma/cirugía , Adulto , Irradiación Craneana , Dacarbazina/análogos & derivados , Dacarbazina/uso terapéutico , Descompresión Quirúrgica , Agonistas de Dopamina/uso terapéutico , Femenino , Estudios de Seguimiento , Hormona Liberadora de Gonadotropina/análogos & derivados , Humanos , Hipofisectomía/métodos , Masculino , Neoplasia Residual , Neoplasias Hipofisarias/tratamiento farmacológico , Neoplasias Hipofisarias/radioterapia , Neoplasias Hipofisarias/cirugía , Complicaciones Posoperatorias/tratamiento farmacológico , Complicaciones Posoperatorias/etiología , Radiocirugia , Radioterapia de Intensidad Modulada , Somatostatina/análogos & derivados , Temozolomida
12.
Endocrinol. nutr. (Ed. impr.) ; 57(2): 71-81, feb. 2010. ilus, tab
Artículo en Español | IBECS | ID: ibc-80312

RESUMEN

Los adenomas hipofisarios clínicamente no funcionantes son los macroadenomas más frecuentes en adultos. Se caracterizan por no acompañarse de hipersecreción hormonal detectable en plasma y diagnosticarse cuando aparece sintomatología compresiva o déficits hormonales. El tratamiento de elección es la resección quirúrgica, pero es frecuente que no sea curativa o haya recidivas y se requieran tratamientos adicionales. Los fármacos tienen escasa eficacia y solo han conseguido pequeñas reducciones tumorales en algunos pacientes. Debe considerarse tratamiento con RT postquirúrgica en pacientes con grandes restos o crecimiento de los restos durante el seguimiento. Las técnicas estereotáxicas se han desarrollado para disminuir las complicaciones de la irradiación. En los microadenomas el crecimiento no es frecuente, por lo que solo se recomienda observación (AU)


Clinically nonfunctioning adenomas are the most frequent pituitary macroadenomas in adults. These tumors are characterized by the absence of detectable hormonal hypersecretion and are diagnosed when compression symptoms or hormonal deficiencies occur. The treatment of choice of macroadenomas is surgery, but tumoral resection is often incomplete or the patient develops tumoral recurrence. Medical therapy has been shown to produce modest tumoral reduction in some patients. Postoperative irradiation should be considered in patients with large tumoral remnants or enlargement of remnants during follow-up. Stereotactic radiotherapy has been developed to diminish the long-term complications of radiotherapy. Microadenomas tend to remain small and surveillance alone is recommended. The present article reviews the results of medical, surgical and radiation treatments (AU)


Asunto(s)
Humanos , Masculino , Adulto , Adenoma/terapia , Neoplasias Hipofisarias/terapia , Irradiación Craneana , Descompresión Quirúrgica , Agonistas de Dopamina/uso terapéutico , Estudios de Seguimiento , Hipofisectomía/métodos , Neoplasia Residual
13.
Endocrinol Nutr ; 56(8): 412-7, 2009 Oct.
Artículo en Español | MEDLINE | ID: mdl-19959151

RESUMEN

INTRODUCTION: High-dose cabergoline therapy has been related to cardiac valve regurgitation in patients with Parkinson's disease. AIMS: To perform a systematic analysis of reports on low-dose cabergoline treatment in hyperprolactinemia and its effect on the cardiac valves. RESULTS: None of the seven reports analyzed, including 463 patients in total, found clinically significant valve regurgitation. Only one report found moderate tricuspid valve regurgitation, and other two reports found mild tricuspid valve regurgitation. An increase in the mitral tenting area was documented in only one of two reports. Valve thickening and calcifications were found in only one study. CONCLUSIONS: Cabergoline seems to be safe at the doses employed in hyperprolactinemic patients. There is a higher prevalence of tricuspid regurgitation, detected by systematic echocardiography, but this abnormality is asymptomatic. Although prospective longitudinal studies are needed, vigilance of these patients is recommended, especially those treated with high-dose cabergoline.


Asunto(s)
Agonistas de Dopamina/uso terapéutico , Ergolinas/efectos adversos , Ergolinas/uso terapéutico , Enfermedades de las Válvulas Cardíacas/inducido químicamente , Hiperprolactinemia/tratamiento farmacológico , Adulto , Anciano , Antiparkinsonianos/efectos adversos , Antiparkinsonianos/uso terapéutico , Cabergolina , Estudios de Casos y Controles , Femenino , Enfermedades de las Válvulas Cardíacas/diagnóstico por imagen , Enfermedades de las Válvulas Cardíacas/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Hipofisarias/tratamiento farmacológico , Neoplasias Hipofisarias/metabolismo , Prevalencia , Prolactina/metabolismo , Prolactinoma/tratamiento farmacológico , Prolactinoma/metabolismo , Ultrasonografía
14.
Endocrinol. nutr. (Ed. impr.) ; 56(8): 412-417, oct. 2009. tab
Artículo en Español | IBECS | ID: ibc-78732

RESUMEN

Introducción: La cabergolina a dosis elevadas se ha relacionado con insuficiencia valvular y retracción y engrosamiento valvular en pacientes con enfermedad de Parkinson. Objetivos: Realizar un análisis sistemático de las publicaciones sobre pacientes con hiperprolactinemia tratados con cabergolina y su efecto en las válvulas cardíacas. Resultados: Ninguna de las 7 series revisadas, con 463 pacientes en total, detectó insuficiencia valvular clínicamente significativa. Se encontró insuficiencia tricuspídea (IT) moderada sólo en un estudio, e IT ligera en otras 2 publicaciones. El aumento del área de tenting mitral sólo se ha demostrado en uno de los dos estudios realizados. Hubo calcificaciones y engrosamiento valvular solamente en una de las series. Conclusiones: La cabergolina parece ser segura a las dosis empleadas en la hiperprolactinemia. Hay aumento de prevalencia de IT como hallazgo ecográfico, pero es asintomática. Aunque se precisan estudios longitudinales prospectivos, se recomienda la vigilancia de los pacientes tratados, especialmente con dosis elevadas (AU)


Introduction: High-dose cabergoline therapy has been related to cardiac valve regurgitation in patients with Parkinson’s disease. Aims: To perform a systematic analysis of reports on low-dose cabergoline treatment in hyperprolactinemia and its effect on the cardiac valves. Results: None of the seven reports analyzed, including 463 patients in total, found clinically significant valve regurgitation. Only one report found moderate tricuspid valve regurgitation, and other two reports found mild tricuspid valve regurgitation. An increase in the mitral tenting area was documented in only one of two reports. Valve thickening and calcifications were found in only one study. Conclusions: Cabergoline seems to be safe at the doses employed in hyperprolactinemic patients. There is a higher prevalence of tricuspid regurgitation, detected by systematic echocardiography, but this abnormality is asymptomatic. Although prospective longitudinal studies are needed, vigilance of these patients is recommended, especially those treated with high-dose cabergoline (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Agonistas de Dopamina/uso terapéutico , Ergolinas/efectos adversos , Ergolinas/uso terapéutico , Enfermedades de las Válvulas Cardíacas/inducido químicamente , Hiperprolactinemia/tratamiento farmacológico
15.
Endocrinol Nutr ; 56(3): 132-5, 2009 Mar.
Artículo en Español | MEDLINE | ID: mdl-19627726

RESUMEN

Primary hyperparathyroidism is caused by an adenoma/hyperplasia in the parathyroid glands in which hypercalcemia is mainly due to an increased secretion of parathormone (PTH). The only definitive treatment is surgery. There are some patients at high surgical risk or who refuse surgery, and whose hypercalcemia cannot be controlled with conventional medical therapy such as hydration, diuretics and/or oral biphosphonates. We suggest the use of two drugs indicated for the treatment of hypercalcemia of other etiologies: zoledronic acid, a parenteral bisphosphonate, and cinacalcet, a calcimimetic agent that reduces PTH secretion. We present the case of a woman with hypercalcemia due to primary hyperparathyroidism caused by an adenoma, who was treated with both drugs.


Asunto(s)
Adenoma/complicaciones , Difosfonatos/uso terapéutico , Hipercalcemia/tratamiento farmacológico , Hiperparatiroidismo Primario/etiología , Imidazoles/uso terapéutico , Naftalenos/uso terapéutico , Neoplasias de las Paratiroides/complicaciones , Anciano de 80 o más Años , Neoplasias de la Mama/cirugía , Carcinoma/cirugía , Carcinoma de Células Renales/fisiopatología , Cinacalcet , Comorbilidad , Contraindicaciones , Quimioterapia Combinada , Femenino , Fluidoterapia , Furosemida/uso terapéutico , Humanos , Hipercalcemia/etiología , Pruebas de Función Renal , Neoplasias Renales/fisiopatología , Paratiroidectomía , Negativa del Paciente al Tratamiento , Ácido Zoledrónico
16.
Endocrinol. nutr. (Ed. impr.) ; 56(3): 132-135, mar. 2009. graf
Artículo en Español | IBECS | ID: ibc-61699

RESUMEN

El hiperparatiroidismo primario es una enfermedad causada por un adenoma/hiperplasia en las glándulas paratiroides, en la que la hipercalcemia debida a una excesiva secreción de parathormona (PTH) es el rasgo principal, y cuyo único tratamiento definitivo es la cirugía. Hay pacientes en los que la cirugía supone un gran riesgo, o que la rechazan, y en los cuales la hipercalcemia no puede ser controlada mediante el tratamiento médico convencional con hidratación, diuréticos y/o bisfosfonatos. Proponemos el uso de dos fármacos indicados en el tratamiento de la hipercalcemia de otras etiologías: el ácido zoledrónico, bisfosfonato de uso parenteral, y el cinacalcet, calcimimético que disminuye la secreción de PTH. Presentamos el caso de una mujer con hipercalcemia por un hiperparatiroidismo primario causado por un adenoma, tratado con ambos fármacos (AU)


Primary hyperparathyroidism is caused by an adenoma/hyperplasia in the parathyroid glands in which hypercalcemia is mainly due to an increased secretion of parathormone (PTH). The only definitive treatment is surgery. There are some patients at high surgical risk or who refuse surgery, and whose hypercalcemia cannot be controlled with conventional medical therapy such as hydration, diuretics and/or oral biphosphonates. We suggest the use of two drugs indicated for the treatment of hypercalcemia of other etiologies: zoledronic acid, a parenteral bisphosphonate, and cinacalcet, a calcimimetic agent that reduces PTH secretion. We present the case of a woman with hypercalcemia due to primary hyperparathyroidism caused by an adenoma, who was treated with both drugs (AU)


Asunto(s)
Humanos , Femenino , Anciano de 80 o más Años , Hiperparatiroidismo Primario/tratamiento farmacológico , Difosfonatos/farmacocinética , Hormona Paratiroidea , Neoplasias de las Paratiroides , Hipercalcemia/prevención & control
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