Activation in the family of Candida rugosa isolipases by polyethylene glycol

Disponible en: http://www.xtal.iqfr.csic.es/publications/jmolcat2005.pdfWe have investigated activation of two isoenzymes (lip1 and lip3) from Candida rugosa in polyethylene glycol (PEG) media. Aqueous solutions of PEG 8000 and 20,000 activate lip3 but not lip1 from C. rugosa. Maximum activation (260%) of lip3 requires 6 h of pre-incubation with PEG 8000 (4%, w/v). PEG seems to shift the equilibrium between the open and the closed forms of lip3 towards the active conformation. Inhibition experiments demonstrate that ligands have easier access to the lip3 active site than to the lip1 active site, both in the presence and the absence of PEG. The presence of PEG in the crystallization medium is responsible for reported differences in the crystal structures of lip1 and lip3. A comparative analysis of crystallographic models of lip1 and lip3 suggests a role for PEG in activation of lip3 and further stabilization of the activated/open form via dimerization in aqueous media.This work has been financed by the Spanish CICYT (PB92/0495 and BIO 96/0837). A predoctoral fellowship for M.F.P. was provided by the Autonomous Community of Madrid (Spain).Peer reviewe

Tectonic implications of paleontologic dating of Cretaceous-Danian sections of Eastern Cuba

The sedimentary rocks intercalated in volcanic and metavolcanic sections of Mayarí-Baracoa and Sierra del Purial Mountains (Eastern Cuba), yielded Cretaceous through Danian microfossils. In the Mayarí Mountains the Téneme Fm consists of basalts and hyaloclastites with minor intercalations of well-bedded foliated limestone and shaly limestone that in the type area contain a Turonian or early Coniacian planktonic foraminifera assemblage. In the Morel area (Moa-Baracoa massif), back-arc pillow basalts with ribbon cherts include a late Turonian or Coniacian limestone bed intercalated with interbedded organic-rich calcareous shales near the top. The upper part of the Coniacian (?)-Campanian Santo Domingo Fm crops out west of Moa and it consists of finegrained well-bedded volcaniclastic rocks with two intercalated lenses of coarse-grained impure biocalcirudites to biocalcarenites. These rocks yielded a mixed penecontemporaneous planktonic and benthonic microfossil assemblage attributed to the lower part of the late Campanian (Globotruncanita calcarata Zone). At Sierra del Purial, crystalline limestones embedded within the metavulcano-sedimentary Río Baracoa section (Purial metamorphic complex) yielded Campanian microfossils. The Maastrichtian Yaguaneque (=Cañas) limestones crop out extensively in both Mayarí-Baracoa and Purial Mountains. All the formations previously mentioned unconformably overlie and tectonically intermingle with the late Maastrichtian-early Danian clastic rocks of the Mícara and La Picota Fms. Our new dates demonstrate that in the Greater Antilles the PIA (Primitive Island Arc-tholeiite) recorded by the Téneme Fm would be Late Cretaceous in age in opposition to the Lower Cretaceous age proposed for the PIA basalts. The protolith of the Purial metamorphic complex is probably Maastrichtian-early Danian, but certainly Campanian and older in age. This fact suggests that the metamorphism that affected the Purial rocks took place probably in the late Maastrichtian and was coeval with the detachment, exhumation and emplacement of mafic-ultramafic thrust-sheet bodies. This event recorded in Eastern Cuba/Western Hispaniola and Guatemala might have been related to the insertion of thick oceanic ridges into the subduction zone

Prolapso de la glándula lacrimal del tercer párpado

El prolapso de la glándula lacrimal del tercer párpado es relativamente frecuente en oftalmología canina. La exéresis glandular es una técnica sencilla, aunque puede presentar complicaciones a largo plazo. La adenopexia debería ser la primera elección quirúrgica, su resultado depende de una adecuada exposición de la esclerótica, del tamaño de la glándula y de la calidad del material de sutura empleado.Protrusion of the membrane nictitans gland is a common occurrence in veterinary ophthalmology. Although excision of the gland is an easy technique, it can develop serious further complications. Adenopexia should be the first surgical election, iss success depends on the clear sclera exposure, the gland size and the quality of the suture material employed

Servidor de datos y página web para el aprendizaje de SIG en la ingeniería forestal

Los Sistemas de Información geográfica (SIG) son una herramienta de trabajo habitual en el ámbito de la ingeniería forestal, tanto en la faceta de redacción de proyectos, como en la investigación sobre el medio ambiente y el territorio. Cada vez hay más información cartográfica disponible desde servidores de diferentes instituciones, por lo que consideramos que es muy útil contar con una herramienta de organización de la información. En el trabajo que se presenta, se pretende proporcionar a los estudiantes e investigadores en materia forestal un portal que contenga información actualizada y ordenada sobre los recursos existentes compatibles con los SIG. Por tanto constituiráuna herramienta de apoyo que facilitarála fase de documentación, búsqueda de datos compatibles y aprendizaje de las herramientas que sirven de base para el desarrollo de cualquier trabajo técnico o de investigación relacionado con el medio ambiente y el territorio que se apoye en los SIG

Understanding hydrodechlorination of chloromethanes. Past and future of the technology

Chloromethanes are a group of volatile organic compounds that are harmful to the environment and human health. Abundant studies have verified that hydrodechlorination might be an effective treatment to remove these chlorinated pollutants. The most outstanding advantages of this technique are the moderate operating conditions used and the possibility of obtaining less hazardous valuable products. This review presents a global analysis of experimental and theoretical studies regarding the hydrodechlorination of chloromethanes. The catalysts used and their synthesis methods are summarized. Their physicochemical properties are analyzed in order to deeply understand their influence on the catalytic performance. Moreover, the main causes of the catalyst deactivation are explained, and prevention and regeneration methods are suggested. The reaction systems used and the effect of the operating conditions on the catalytic activity are also analyzed. Besides, the mechanisms and kinetics of the process at the atomic level are reviewed. Finally, a new perspective for the upgrading of chloromethanes, via hydrodechlorination, to valuable hydrocarbons for industry, such as light olefins, is discussedThe authors gratefully acknowledge financial support through research projects SI1/PJI/2019-00487 (Comunidad de Madrid/UAM) and CTM2017-85498-R (FEDER/Ministerio de Ciencia, Innovación y Universidades-Agencia Estatal de Investigación). M. Martín Martínez acknowledges a postdoctoral grant, 2017-T2/AMB-5668, from the Comunidad de Madrid “Atracción de talento investigador” programme. S. Liu acknowledges MINECO for his research grant PRE2018-08442

Verificación artroscópica del diagnóstico por resonancia magnética de las lesiones meniscales

La utilización de la Imagen por Resonancia Magnética (IRM) como prueba diagnóstica en la patología de la rodilla, se presenta como alternativa no invasiva fundamental. Se ha diseñado un protocolo a doble ciego junto al servicio de radiodiagnóstico de nuestro hospital a través del cual se han evaluado un total de 31 pacientes donde los hallazgos de la IRM son contrastados con la exploración artroscópica posterior. Para el menisco interno, la precisión diagnóstica de la IRM es del 93 % y del 87% para el externo. Como conclusiones de mayor relieve, la sensibilidad de la exploración fue del 90% para el interno y del 75% para el externo y respecto a la especificidad, en el interno resultó ser del 100% y del 91% en el externo. Los valores predictivo negativo y positivo fueron respectivamente del 85 y 100% en el menisco interno y del 84 y 75% en el externo. Se encontró mayor dificultad diagnóstica en la porción anterior del menisco externo y falta de precisión ocasional en definir el tipo y extensión de la lesión.The use of Magnetic Resonance Imaging (MIR) as a diagnostic trial in the pathology of the knee, has become an important non invasive alternative. We have designed a double blind protocol with the Department of Radiology through we have evaluated 31 patients analyzing the MRI results in relation with the arthroscopic findings. For the medial meniscus, the accuracy of the MRI was 93 % and 87% for the lateral. As main conclusions, the sensibility was 90% for the medial meniscus and 75% for the lateral one and about specificity, we found a result of 100% for the medial meniscus and 91% for the lateral. The negative and positive predictive values were respectively 85% and 100% for the medial and 84% and 75% for the lateral. We noted more diagnostic difficulties in the anterior portion of lateral meniscus and lack of precission in the determination of the type and extension of the meniscal injury

Reconstrucción del ligamento cruzado anterior con plastia mixta de semitendinoso y fibra de Kennedy-Lad

—Se han evaluado los resultados de la reconstrucción del ligamento cruzado anterior (LCA) con una plastia mixta de tendón del semitendinoso y fibra sintética de KennedyLAD en veinticinco pacientes con un mínimo de dos años de seguimiento postoperatorio (media de treinta y ocho meses). Se trataba en todos los casos de lesiones crónicas donde la cirugía consistió en la reconstrucción del LCA y meniscectomías parciales cuando fueron necesarias. La evaluación se llevó a cabo mediante pruebas funcionales (Lysholm) y clínicas (Marshall), pruebas de estabilidad manual (Lachman, pivot, cajón neutro anterior), medidas instrumentales de estabilidad con artrómetro (KT-1000), índice de actividad y apreciación subjetiva. Los datos indican que el comportamiento de la plastia es adecuado en el 92% de los casos proporcionando a los pacientes una función articular satisfactoria en su vida diaria incluyendo la actividad deportiva.The authors assess the results of the anterior cruciate ligament (ACL) reconstruction by means of a semitendinous tendon and Kennedy LAD composite graft. Minimum followup has been two years (mean of thirty eight months). In every cases the lesion was considered as chronic and surgery consisted of ACL reconstruction and partial meniscectomy if neccessary. Studies performed to asses the results included: functional (Lysholm) and clinical (Marshall) tests, manual stability tests (Lachman, pivot-shift, neutral anterior drawer), instrumented stability measurement (KT-1000 arthrometer), activity score and subjective patient self-assessment. The data collected indicate that the performance of the composite graft is adequate in 92% of the cases, allowing the patients a satisfactory knee joint function in their daily life including sporting activities

Reconstructing the impact of human activities in a NW Iberian Roman mining landscape for the last 2500 years

This article was made available through the Brunel Open Access Publishing Fund.Little is known about the impact of human activities during Roman times on NW Iberian mining landscapes beyond the geomorphological transformations brought about by the use of hydraulic power for gold extraction. We present the high-resolution pollen record of La Molina mire, located in an area intensely used for gold mining (Asturias, NW Spain), combined with other proxy data from the same peat core to identify different human activities, evaluate the strategies followed for the management of the resources and describe the landscape response to human disturbances. We reconstructed the timing and synchronicity of landscape changes of varying intensity and form occurred before, during and after Roman times. An open landscape was prevalent during the local Late Iron Age, a period of relatively environmental stability. During the Early Roman Empire more significant vegetation shifts took place, reflected by changes in both forest (Corylus and Quercus) and heathland cover, as mining/metallurgy peaked and grazing and cultivation increased. In the Late Roman Empire, the influence of mining/metallurgy on landscape change started to disappear. This decoupling was further consolidated in the Germanic period (i.e., Visigothic and Sueve domination of the region), with a sharp decrease in mining/metallurgy but continued grazing. Although human impact was intense in some periods, mostly during the Early Roman Empire, forest regeneration occurred afterwards: clearances were local and short-lived. However, the Roman mining landscape turned into an agrarian one at the onset of the Middle Ages, characterized by a profound deforestation at a regional level due to a myriad of human activities that resulted in an irreversible openness of the landscape. © 2014 The Authors