Inflammatory myopathy and severe rhabdomyolysis induced by leuprolide acetate therapy for prostate cancer: a case report

Introduction Leuprolide acetate is a synthetic analog of gonadotropin-releasing hormone used for the treatment of prostate cancer. Its side effects are hot flashes, nausea, and fatigue. We report a case of a patient with proximal inflammatory myopathy accompanied by severe rhabdomyolysis and renal failure following the second application of leuprolide acetate. Drug withdrawal and steroid therapy resulted in remission within six weeks of the diagnosis. To the best of our knowledge, our case report describes the second case of leuprolide acetate-induced inflammatory myopathy and the first case of severe leuprolide acetate-induced rhabdomyolysis and renal failure in the literature. Case presentation A 64-year-old Swiss Caucasian man was admitted to the hospital because of progressive proximal muscle weakness, dyspnea, and oliguria. He had been treated twice with leuprolide acetate in monthly doses. We performed a muscle biopsy, which excluded other causes of myopathy. The patient's renal failure and rhabdomyolysis were treated with rehydration and steroid therapy. Conclusion The aim of our case report is to highlight the rare but severe side effects associated with leuprolide acetate therapy used to treat patients with inflammatory myopathy: severe rhabdomyolysis and renal failure.

Common and unexpected findings in mummies from ancient Egypt and South America as revealed by CT

Computed tomography (CT) has proved to be a valuable investigative tool for mummy research and is the method of choice for examining mummies. It allows for noninvasive insight, especially with virtual endoscopy, which reveals detailed information about the mummy's sex, age, constitution, injuries, health, and mummification techniques used. CT also supplies three-dimensional information about the scanned object. Mummification processes can be summarized as "artificial," when the procedure was performed on a body with the aim of preservation, or as "natural," when the body's natural environment resulted in preservation. The purpose of artificial mummification was to preserve that person's morphologic features by delaying or arresting the decay of the body. The ancient Egyptians are most famous for this. Their use of evisceration followed by desiccation with natron (a compound of sodium salts) to halt putrefaction and prevent rehydration was so effective that their embalmed bodies have survived for nearly 4500 years. First, the body was cleaned with a natron solution; then internal organs were removed through the cribriform plate and abdomen. The most important, and probably the most lengthy, phase was desiccation. After the body was dehydrated, the body cavities were rinsed and packed to restore the body's former shape. Finally, the body was wrapped. Animals were also mummified to provide food for the deceased, to accompany the deceased as pets, because they were seen as corporal manifestations of deities, and as votive offerings. Artificial mummification was performed on every continent, especially in South and Central America.

A 4-year study on clinical characteristics of children hospitalized with rotavirus gastroenteritis

Rotavirus (RV) is a frequent cause of severe gastroenteritis (GE) in children. With the licensure of new RV vaccines, data on the burden of disease are important regarding immunization strategies. We reviewed the medical records of children hospitalized with RV infection in our institution between July 2002 and March 2006. Relevant data were extracted in a standardized fashion from records of hospitalized children with a positive RV antigen test in a stool sample. Severity of disease was graded by the 20-point Vesikari score. Population data were obtained from the Federal Office of Statistics. Six hundred eighty-six RVGE were identified and records of 608 hospitalizations (in 607 children) were available. In 539 (89%) cases, RVGE was the primary reason for hospitalization and 69 (11%) were nosocomial infections; yearly peaks occurred between February and May. Cumulative incidence of RVGE was 26.7/1,000 children <3 years of age. Median age of 539 children (55.6% male) with primary RVGE was 1.4 years and median stay in the hospital for both community acquired and nosocomial RVGE was 4 days (interquartile range 3-5). Thirtypercent and 94% of RV hospitalizations were in children <1 and <3 years of age, respectively. Mean Vesikari score was 15 (range 6-20; 96% >11). Intravenous fluids were administered in 378 (70%) patients, 130 (24%) patients were rehydrated via nasogastral tube, and 31 (5.7%) received rehydration by mouth. RVGE causes a substantial burden in children with an estimated risk for hospitalization due to RVGE of one in 37 children <3 years of age.

Performance recovery from exercise: A review from a statistical point of view

Background. Research into methods for recovery from fatigue due to exercise is a popular topic among sport medicine, kinesiology and physical therapy. However, both the quantity and quality of studies and a clear solution of recovery are lacking. An analysis of the statistical methods in the existing literature of performance recovery can enhance the quality of research and provide some guidance for future studies. Methods: A literature review was performed using SCOPUS, SPORTDiscus, MEDLINE, CINAHL, Cochrane Library and Science Citation Index Expanded databases to extract the studies related to performance recovery from exercise of human beings. Original studies and their statistical analysis for recovery methods including Active Recovery, Cryotherapy/Contrast Therapy, Massage Therapy, Diet/Ergogenics, and Rehydration were examined. Results: The review produces a Research Design and Statistical Method Analysis Summary. Conclusion: Research design and statistical methods can be improved by using the guideline from the Research Design and Statistical Method Analysis Summary. This summary table lists the potential issues and suggested solutions, such as, sample size calculation, sports specific and research design issues consideration, population and measure markers selection, statistical methods for different analytical requirements, equality of variance and normality of data, post hoc analyses and effect size calculation.^

A systematic review of the evidence for use of herbal medicine for the treatment of acute diarrhea

Background. Acute diarrhea (AD) is an important cause of morbidity and mortality among both children and adults. An ideal antidiarrheal treatment should be safe, effective, compatible with Oral Rehydration Solution, and inexpensive. Herbal medicines, if effective, should fit these criteria as well or better than standard treatment. ^ Objective. The objective of the present study was to assess the effectiveness of plant preparations in patients with AD in reports of randomized and non-randomized controlled trials. ^ Aims. The aims of the present study were to identify effective antidiarrheal herbs and to identify potential antidiarrheal herbs for future studies of efficacy through well designed clinical trials in human populations. ^ Methods. Nineteen published studies of herbal management of AD were examined to identify effective plant preparations. Ten plant preparations including Berberine (Berberis aristata), tormentil root ( Potentialla tormentilla), baohauhau (from the baobaosan plant), carob (Ceratonia siliqua), pectin (Malus domestica), wood creosote (Creosote bush), guava (Psidium guajava L.), belladonna (Atropa belladonna), white bean (Phaseolis vulgaris), and wheat (Triticum aestivum) were identified. ^ Results. Qualitative data analysis of nineteen clinical trials indicated berberine’s potentially valuable antisecretory effects against diarrhea caused by Vibrio cholerae and enterotoxigenic Escherichia coli. Tormentil root showed significant efficacy against rotavirus-induced diarrhea; carob exhibited antidiarrheal properties not only by acting to detoxify and constipate but by providing a rich source of calories; guava and belladonna are antispasmodics and have been shown to relieve the symptoms of AD. Finally, white bean and wheat yielded favorable clinical and dietary outcomes in children with diarrhea. ^ Conclusion. The present study is the first to review the evidence for use of herbal compounds for treatment of AD. Future randomized controlled trials are needed to evaluate their efficacy and safety.^

Study of rural leadership and implications for community participation and development in the health and family planning programs in Bangladesh

The vast majority of Bangladesh are poor and are unable even to provide for the most basic human needs. These are the landless and marginal farmers of Bangladesh. They constitute 70% of the rural population, which in turn constitute about 90% of the country's population.^ Effective development of Bangladesh would largely mean the development of the landless and marginal farmers. Past efforts of development in this section of the population, including that of the government, have not succeeded. One of the development goals of the government of Bangladesh is to improve the quality of life of the rural population through health and population control measures. Overpopulation, malnutrition and diarrhea are the major impediments to socioeconomic development in Bangladesh.^ The current study was designed to identify whether there is effective opinion leadership among the marginal and landless peasants affecting decisions on acceptance or nonacceptance of family planning methods and oral rehydration therapy (ORT) in the selected rural areas of Bangladesh. The study was conducted in eight randomly selected villages with funding from the Ministry of Health and Family Planning, government of Bangladesh. One hundred twenty-five opinion leaders were interviewed after they were identified by 408 rural couples owning land less than 2 acres and wives' age below 50. The study was conducted in two phases; couples' interview preceded that of the leaders.^ Findings of the study reveal that the opinion leaders influencing adoption of health and family planning among the landless and marginal farmers belong to the same class. Theses opinion leaders own land much less than the rich farmers and the formal leaders in the rural areas. Majority of these of opinion leaders are friends, neighbors and relatives, some are other persons who are businessmen and professionals like doctors, while the rest few are the field workers of health and family planning. Source of influence as a factor contribute most in differentiating use and non-use of family planning and ORT among both couples and leaders. The most frequent sources of influence referred by the couples and the leaders are the field workers of health and family planning, followed by the peer opinion leaders (friends, neighbors, relatives) and spouse.^ The opinion leaders do not differ much from the poor couples on land holding, a strong indicator of economic status, they however differ considerably on social factors such as family planning practice, education, and exposure to mass media.^ The study suggests that future development efforts in Bangladesh have to ensure community participation by the landless and marginal farmers and opinion leaders belonging to their class. ^

Effect of fibers and whole grain content on quality attributes

Incorporation of fiber in cereals may lead to quality issues, thus decreasing consumer acceptance. This is partially due to deterioration of the microstructure, one of the primary quality attributes of cereals. The objective of this study was to better understand the mechanisms by which dietary fibers affect the quality of cereal products during extrusioncooking. The study quantified the effect of amount and type of fiber and whole grain on (i) texture, (ii) structure, and (iii) rehydration properties of extruded cereals. New innovative methods were applied and combined with traditional techniques to characterize both the structure and the rehydration properties. Extruded cereals were produced using a starch-based recipe (whole and wheat flours) and two sources of fibers (oat bran concentrate and wheat bran). The oat and wheat bran levels used in this study were 0, 10, and 20%. The different mixtures were extruded in a pilot twinscrew extruder BC21 (Clextral) and then sugar coated after drying. Mechanical properties of extruded cereals were investigated by compression test. The cellular structure was observed by X-ray tomography. The quality of coating (thickness, homogeneity) was analyzed by optical coherence tomography. The rehydration properties of such cereals in milk were evaluated by magnetic resonance imaging and optical coherence tomography. This work revealed that structure assessment of extruded cereals may lead to a better understanding of the effect of fiber addition on texture and rehydration properties. The application of innovative methods, such as optical coherence tomography and magnetic resonance imaging, was found to be useful to quantify the structural properties.

A multi-criteria optimization and decision-making approach for improvement of food engineering processes.

The objective of this study was to propose a multi-criteria optimization and decision-making technique to solve food engineering problems. This technique was demostrated using experimental data obtained on osmotic dehydratation of carrot cubes in a sodium chloride solution. The Aggregating Functions Approach, the Adaptive Random Search Algorithm, and the Penalty Functions Approach were used in this study to compute the initial set of non-dominated or Pareto-optimal solutions. Multiple non-linear regression analysis was performed on a set of experimental data in order to obtain particular multi-objective functions (responses), namely water loss, solute gain, rehydration ratio, three different colour criteria of rehydrated product, and sensory evaluation (organoleptic quality). Two multi-criteria decision-making approaches, the Analytic Hierarchy Process (AHP) and the Tabular Method (TM), were used simultaneously to choose the best alternative among the set of non-dominated solutions. The multi-criteria optimization and decision-making technique proposed in this study can facilitate the assessment of criteria weights, giving rise to a fairer, more consistent, and adequate final compromised solution or food process. This technique can be useful to food scientists in research and education, as well as to engineers involved in the improvement of a variety of food engineering processes.

Application of NMR techniques for the evaluation of fruit internal quality and physical properties of food

Los alimentos son sistemas complejos, formados por diversas estructuras a diferentes escalas: macroscópica y microscópica. Muchas propiedades de los alimentos, que son importantes para su procesamiento, calidad y tratamiento postcosecha, están relacionados con su microestructura. La presente tesis doctoral propone una metodología completa para la determinación de la estructura de alimentos desde un punto de vista multi-escala, basándose en métodos de Resonancia Magnética Nuclear (NMR). Las técnicas de NMR son no invasivas y no destructivas y permiten el estudio tanto de macro- como de microestructura. Se han utilizado distintos procedimientos de NMR dependiendo del nivel que se desea estudiar. Para el nivel macroestructural, la Imagen de Resonancia Magnética (MRI) ha resultado ser muy útil para la caracterización de alimentos. Para el estudio microestructural, la MRI requiere altos tiempos de adquisición, lo que hace muy difícil la transferencia de esta técnica a aplicaciones en industria. Por tanto, la optimización de procedimientos de NMR basados en secuencias relaxometría 2D T1/T2 ha resultado ser una estrategia primordial en esta tesis. Estos protocolos de NMR se han implementado satisfactoriamente por primera vez en alto campo magnético. Se ha caracterizado la microestructura de productos alimentarios enteros por primera vez utilizando este tipo de protocolos. Como muestras, se han utilizado dos tipos de productos: modelos de alimentos y alimentos reales (manzanas). Además, como primer paso para su posterior implementación en la industria agroalimentaria, se ha mejorado una línea transportadora, especialmente diseñada para trabajar bajo condiciones de NMR en trabajos anteriores del grupo LPF-TAGRALIA. Se han estudiado y seleccionado las secuencias más rápidas y óptimas para la detección de dos tipos de desórdenes internos en manzanas: vitrescencia y roturas internas. La corrección de las imágenes en movimiento se realiza en tiempo real. Asimismo, se han utilizado protocolos de visión artificial para la clasificación automática de manzanas potencialmente afectadas por vitrescencia. El presente documento está dividido en diferentes capítulos: el Capítulo 2 explica los antecedentes de la presente tesis y el marco del proyecto en el que se ha desarrollado. El Capítulo 3 recoge el estado del arte. El Capítulo 4 establece los objetivos de esta tesis doctoral. Los resultados se dividen en cinco sub-secciones (dentro del Capítulo 5) que corresponden con los trabajos publicados bien en revistas revisadas por pares, bien en congresos internacionales o bien como capítulos de libros revisados por pares. La Sección 5.1. es un estudio del desarrollo de la vitrescencia en manzanas mediante MRI y lo relaciona con la posición de la fruta dentro de la copa del árbol. La Sección 5.2 presenta un trabajo sobre macro- y microestructura en modelos de alimentos. La Sección 5.3 es un artículo en revisión en una revista revisada por pares, en el que se hace un estudio microestrcutural no destructivo mediante relaxometría 2D T1/T2. la Sección 5.4, hace una comparación entre manzanas afectadas por vitrescencia mediante dos técnicas: tomografía de rayos X e MRI, en manzana. Por último, en la Sección 5.5 se muestra un trabajo en el que se hace un estudio de secuencias de MRI en línea para la evaluación de calidad interna en manzanas. Los siguientes capítulos ofrecen una discusión y conclusiones (Capítulo 6 y 7 respectivamente) de todos los capítulos de esta tesis doctoral. Finalmente, se han añadido tres apéndices: el primero con una introducción de los principios básicos de resonancia magnética nuclear (NMR) y en los otros dos, se presentan sendos estudios sobre el efecto de las fibras en la rehidratación de cereales de desayuno extrusionados, mediante diversas técnicas. Ambos trabajos se presentaron en un congreso internacional. Los resultados más relevantes de la presente tesis doctoral, se pueden dividir en tres grandes bloques: resultados sobre macroestructura, resultados sobre microestructura y resultados sobre MRI en línea. Resultados sobre macroestructura: - La imagen de resonancia magnética (MRI) se aplicó satisfactoriamente para la caracterización de macroestructura. En particular, la reconstrucción 3D de imágenes de resonancia magnética permitió identificar y caracterizar dos tipos distintos de vitrescencia en manzanas: central y radial, que se caracterizan por el porcentaje de daño y la conectividad (número de Euler). - La MRI proveía un mejor contraste para manzanas afectadas por vitrescencia que las imágenes de tomografía de rayos X (X-Ray CT), como se pudo verificar en muestras idénticas de manzana. Además, el tiempo de adquisición de la tomografía de rayos X fue alrededor de 12 veces mayor (25 minutos) que la adquisición de las imágenes de resonancia magnética (2 minutos 2 segundos). Resultados sobre microestructura: - Para el estudio de microestructura (nivel subcelular) se utilizaron con éxito secuencias de relaxometría 2D T1/T2. Estas secuencias se usaron por primera vez en alto campo y sobre piezas de alimento completo, convirtiéndose en una forma no destructiva de llevar a cabo estudios de microestructura. - El uso de MRI junto con relaxometría 2D T1/T2 permite realizar estudios multiescala en alimentos de forma no destructiva. Resultados sobre MRI en línea: - El uso de imagen de resonancia magnética en línea fue factible para la identificación de dos tipos de desórdenes internos en manzanas: vitrescencia y podredumbre interna. Las secuencias de imagen tipo FLASH resultaron adecuadas para la identificación en línea de vitrescencia en manzanas. Se realizó sin selección de corte, debido a que la vitrescencia puede desarrollarse en cualquier punto del volumen de la manzana. Se consiguió reducir el tiempo de adquisición, de modo que se llegaron a adquirir 1.3 frutos por segundos (758 ms por fruto). Las secuencias de imagen tipo UFLARE fueron adecuadas para la detección en línea de la podredumbre interna en manzanas. En este caso, se utilizó selección de corte, ya que se trata de un desorden que se suele localizar en la parte central del volumen de la manzana. Se consiguió reducir el tiempo de adquisicón hasta 0.67 frutos por segundo (1475 ms por fruto). En ambos casos (FLASH y UFLARE) fueron necesarios algoritmos para la corrección del movimiento de las imágenes en tiempo real. ABSTRACT Food is a complex system formed by several structures at different scales: macroscopic and microscopic. Many properties of foods that are relevant to process engineering or quality and postharvest treatments are related to their microstructure. This Ph.D Thesis proposes a complete methodology for food structure determination, in a multiscale way, based on the Nuclear Magnetic Resonance (NMR) phenomenon since NMR techniques are non-invasive and non-destructive, and allow both, macro- and micro-structure study. Different NMR procedures are used depending on the structure level under study. For the macrostructure level, Magnetic Resonance Imaging (MRI) revealed its usefulness for food characterization. For microstructure insight, MRI required high acquisition times, which is a hindrance for transference to industry applications. Therefore, optimization of NMR procedures based on T1/T2 relaxometry sequences was a key strategy in this Thesis. These NMR relaxometry protocols, are successfully implemented in high magnetic field. Microstructure of entire food products have been characterized for the first time using these protocols. Two different types of food products have been studied: food models and actual food (apples). Furthermore, as a first step for the food industry implementation, a grading line system, specially designed for working under NMR conditions in previous works of the LPF-TAGRALIA group, is improved. The study and selection of the most suitable rapid sequence to detect two different types of disorders in apples (watercore and internal breakdown) is performed and the real time image motion correction is applied. In addition, artificial vision protocols for the automatic classification of apples potentially affected by watercore are applied. This document is divided into seven different chapters: Chapter 2 explains the thesis background and the framework of the project in which it has been worked. Chapter 3 comprises the state of the art. Chapter 4 establishes de objectives of this Ph.D thesis. The results are divided into five different sections (in Chapter 5) that correspond to published peered reviewed works. Section 5.1 assesses the watercore development in apples with MRI and studies the effect of fruit location in the canopy. Section 5.2 is an MRI and 2D relaxometry study for macro- and microstructure assessment in food models. Section 5.3 is a non-destructive microstructural study using 2D T1/T2 relaxometry on watercore affected apples. Section 5.4 makes a comparison of X-ray CT and MRI on watercore disorder of different apple cultivars. Section 5.5, that is a study of online MRI sequences for the evaluation of apple internal quality. The subsequent chapters offer a general discussion and conclusions (Chapter 6 and Chapter 7 respectively) of all the works performed in the frame of this Ph.D thesis (two peer reviewed journals, one book chapter and one international congress).Finally, three appendices are included in which an introduction to NMR principles is offered and two published proceedings regarding the effect of fiber on the rehydration of extruded breakfast cereal are displayed. The most relevant results can be summarized into three sections: results on macrostructure, results on microstructure and results on on-line MRI. Results on macrostructure: - MRI was successfully used for macrostructure characterization. Indeed, 3D reconstruction of MRI in apples allows to identify two different types of watercore (radial and block), which are characterized by the percentage of damage and the connectivity (Euler number). - MRI provides better contrast for watercore than X-Ray CT as verified on identical samples. Furthermore, X-Ray CT images acquisition time was around 12 times higher (25 minutes) than MRI acquisition time (2 minutes 2 seconds). Results on microstructure: - 2D T1/T2 relaxometry were successfully applied for microstructure (subcellular level) characterization. 2D T1/T2 relaxometry sequences have been applied for the first time on high field for entire food pieces, being a non-destructive way to achieve microstructure study. - The use of MRI together with 2D T1/T2 relaxometry sequences allows a non-destructive multiscale study of food. Results on on-line MRI: - The use of on-line MRI was successful for the identification of two different internal disorders in apples: watercore and internal breakdown. FLASH imaging was a suitable technique for the on-line detection of watercore disorder in apples, with no slice selection, since watercore is a physiological disorder that may be developed anywhere in the apple volume. 1.3 fruits were imaged per second (768 ms per fruit). UFLARE imaging is a suitable sequence for the on-line detection of internal breakdown disorder in apples. Slice selection was used, as internal breakdown is usually located in the central slice of the apple volume. 0.67 fruits were imaged per second (1475 ms per fruit). In both cases (FLASH and UFLARE) motion correction was performed in real time, during the acquisition of the images.

Conductancia del mesófilo en especies forestales: implicaciones en la respuesta fotosintética a la disponibilidad de agua y luz

La fotosíntesis es el proceso biológico que permite la producción primaria y, por tanto, la vida en nuestro planeta. La tasa fotosintética viene determinada por la ‘maquinaria’ bioquímica y las resistencias difusivas al paso del CO2 desde la atmósfera hasta su fijación en el interior de los cloroplastos. Históricamente la mayor resistencia difusiva se ha atribuido al cierre estomático, sin embargo ahora sabemos, debido a las mejoras en las técnicas experimentales, que existe también una resistencia grande que se opone a la difusión del CO2 desde los espacios intercelulares a los lugares de carboxilación. Esta resistencia, llamada normalmente por su inversa: la conductancia del mesófilo (gm), puede ser igual o incluso superior a la resistencia debida por el cierre estomático. En la presente tesis doctoral he caracterizado la limitación que ejerce la resistencia del mesófilo a la fijación de CO2 en diversas especies forestales y en distintos momentos de su ciclo biológico. En la fase de regenerado, hemos estudiado tres situaciones ambientales relevantes en el mayor éxito de su supervivencia, que son: el déficit hídrico, su interacción con la irradiancia y el paso del crecimiento en la sombra a mayor irradiancia, como puede suceder tras la apertura de un hueco en el dosel forestal. En la fase de arbolado adulto se ha caracterizado el estado hídrico y el intercambio gaseoso en hojas desarrolladas a distinta irradiancia dentro del dosel vegetal durante tres años contrastados en pluviometría. Para cada tipo de estudio se han empleado las técnicas ecofisiológicas más pertinentes para evaluar el estado hídrico y el intercambio gaseoso. Por su complejidad y la falta de un método que permita su cuantificación directa, la gm ha sido evaluada por los métodos más usados, que son: la discriminación isotópica del carbono 13, el método de la J variable, el método de la J constante y el método de la curvatura. Los resultados más significativos permiten concluir que la limitación relativa a la fotosíntesis por la conductancia estomática, del mesófilo y bioquímica es dependiente de la localización de la hoja en el dosel forestal. Por primera vez se ha documentado que bajo estrés hídrico las hojas desarrolladas a la sombra estuvieron más limitadas por una reducción en la gm, mientras que las hojas desarrolladas a pleno sol estuvieron más limitadas por reducción mayor de la conductancia estomática (gsw). Encontramos buena conexión entre el aparato fotosintético foliar y el sistema hídrico debido al alto grado de correlación entre la conductancia hidráulica foliar aparente y la concentración de CO2 en los cloroplastos en distintas especies forestales. Además, hemos mostrado diferentes pautas de regulación del intercambio gaseoso según las particularidades ecológicas de las especies estudiadas. Tanto en brinzales crecidos de forma natural y en el arbolado adulto como en plántulas cultivadas en el invernadero la ontogenia afectó a las limitaciones de la fotosíntesis producidas por estrés hídrico, resultando que las limitaciones estomáticas fueron dominantes en hojas más jóvenes mientras que las no estomáticas en hojas más maduras. La puesta en luz supuso un gran descenso en la gm durante los días siguientes a la transferencia, siendo este efecto mayor según el grado de sombreo previo en el que se han desarrollado las hojas. La aclimatación de las hojas a la alta irradiancia estuvo ligada a las modificaciones anatómicas foliares y al estado de desarrollo de la hoja. El ratio entre la gm/gsw determinó la mayor eficiencia en el uso del agua y un menor estado oxidativo durante la fase de estrés hídrico y su posterior rehidratación, lo cual sugiere el uso de este ratio en los programas de mejora genética frente al estrés hídrico. Debido a que la mayoría de modelos de estimación de la producción primaria bruta (GPP) de un ecosistema no incluye la gm, los mismos están incurriendo en una sobreestimación del GPP particularmente bajo condiciones de estrés hídrico, porque más de la mitad de la reducción en fotosíntesis en hojas desarrolladas a la sombra se debe a la reducción en gm. Finalmente se presenta un análisis de la importancia en las estimas de la gm bajo estrés hídrico de la refijación del CO2 emitido en la mitocondria a consecuencia de la fotorrespiración y la respiración mitocondrial en luz. ABSTRACT Photosynthesis is the biological process that supports primary production and, therefore, life on our planet. Rates of photosynthesis are determined by biochemical “machinery” and the diffusive resistance to the transfer of CO2 from the atmosphere to the place of fixation within the chloroplasts. Historically the largest diffusive resistance was attributed to the stomata, although we now know via improvements in experimental techniques that there is also a large resistance from sub-stomatal cavities to sites of carboxylation. This resistance, commonly quantified as mesophyll conductance (gm), can be as large or even larger than that due to stomatal resistance. In the present PhD I have characterized the limitation exerted by the mesophyll resistance to CO2 fixation in different forest species at different stages of their life cycle. In seedlings, we studied three environmental conditions that affect plant fitness, namely, water deficit, the interaction of water deficit with irradiance, and the transfer of plants grown in the shade to higher irradiance as can occur when a gap opens in the forest canopy. At the stage of mature trees we characterized water status and gas exchange in leaves developed at different irradiance within the canopy over the course of three years that had contrasting rainfall. For each study we used the most relevant ecophysiological techniques to quantify water relations and gas exchange. Due to its complexity and the lack of a method that allows direct quantification, gm was estimated by the most commonly used methods which are: carbon isotope discrimination, the J-variable, constant J and the curvature method The most significant results suggest that the relative limitation of photosynthesis by stomata, mesophyll and biochemistry depending on the position of the leaf within the canopy. For the first time it was documented that under water stress shaded leaves were more limited by a reduction in gm, while the sun-adapted leaves were more limited by stomatal conductance (gsw). The connection between leaf photosynthetic apparatus and the hydraulic system was shown by the good correlations found between the apparent leaf hydraulic conductance and the CO2 concentration in the chloroplasts in shade- and sun-adapted leaves of several tree species. In addition, we have revealed different patterns of gas exchange regulation according to the functional ecology of the species studied. In field grown trees and greenhouse-grown seedlings ontogeny affected limitations of photosynthesis due to water stress with stomatal limitations dominating in young leaves and nonstomatal limitations in older leaves. The transfer to high light resulted in major decrease of gm during the days following the transfer and this effect was greater as higher was the shade which leaves were developed. Acclimation to high light was linked to the leaf anatomical changes and the state of leaf development. The ratio between the gm/gsw determined the greater efficiency in water use and reduced the oxidative stress during the water stress and subsequent rehydration, suggesting the use of this ratio in breeding programs aiming to increase avoidance of water stress. Because most models to estimate gross primary production (GPP) of an ecosystem do not include gm, they are incurring an overestimation of GPP particularly under conditions of water stress because more than half of An decrease in shade-developed leaves may be due to reduction in gm. Finally, we present an analysis of the importance of how estimates of gm under water stress are affected by the refixation of CO2 that is emitted from mitochondria via photorespiration and mitochondrial respiration in light.

Effects of physical exercise and hydration on homocysteine concentrations in physically active male adults = Efectos del ejercicio físico y la hidratación sobre las concentraciones de homocisteína en varones físicamente activos

La presente tesis analiza el efecto del ejercicio físico agudo y la hidratación sobre las concentraciones de homocisteína total (tHcy) y su relación con los parámetros implicados en el metabolismo de la homocisteína como el folato, la vitamina B12, y la creatina en una muestra de varones jóvenes físicamente activos. El trabajo se basa en los resultados del estudio realizado en la Facultad de Ciencias de la Actividad Física y del Deporte de la Universidad Politécnica de Madrid. Para el cual se contó con un total de 29 voluntarios sanos físicamente activos de la Comunidad de Madrid. Los principales resultados de esta tesis son: a) Las concentraciones de tHcy aumentaron después del ejercicio agudo tanto tras una prueba de intensidad máxima (VO2max) como una submáxima (65 % of VO2max) en varones físicamente activos independientemente de las sus concentraciones basales de tHcy. b) Las concentraciones de tHcy disminuyeron 2 h después del ejercicio físico aeróbico submáximo tras aplicar un protocolo de hidratación con una bebida para deportistas. c) Un adecuado protocolo de hidratación durante el ejercicio físico agudo previno el aumento de las concentraciones de tHcy hasta 2 h después del ejercicio. d) Las concentraciones de tHcy aumentaron a las 6 h tras la finalización del ejercicio únicamente en los test en los que no se siguió un protocolo de hidratación durante el ejercicio físico. e) A las 24 h tras el ejercicio, las concentraciones de tHcy volvieron a los niveles basales independientemente de si se aplicó un protocolo de hidratación durante el ejercicio o no. f) Es necesario aclarar si existen mecanismos subyacentes relacionados con el riesgo cardiovascular debido al aumento transitorio de las concentraciones de tHcy inducidas por el ejercicio agudo. Se necesitan más estudios que analicen la relación entre las concentraciones de tHcy después del ejercicio físico agudo y la implicación de la creatina, vitamina B12 y folato como parámetros relacionados en el metabolismo de la homocisteína. El efecto agudo del ejercicio físico aumenta las concentraciones de tHcy por encima de los valores recomendados; sin embargo, un adecuado protocolo de hidratación mantiene las concentraciones a niveles basales y previene el posterior aumento en una muestra de varones adultos físicamente activos. ABSTRACT The current thesis analyzes the effect of exercise and hydration on total homocysteine (tHcy) concentrations and the relationship with the implicated parameters, like folate, vitamin B12, and creatine in physically active male adults. The work is based on the results of the study conducted at the Faculty of Physical Activity and Sport Sciences of the Technical University of Madrid. A total of 29 physically active voluntary healthy males from the Region of Madrid were recruited. The main outcomes of this thesis are: a) tHcy concentrations increased after acute exercise with both, maximal (VO2max) and submaximal (65 % of VO2max) tests in physically active male subjects independently of their baseline tHcy status. b) After 2 h of rehydration with a sport drink, tHcy concentrations, which had previously increased during an acute exercise, decreased significantly, although they didn´t recover to baseline values. c) An adequate hydration protocol during acute aerobic submaximal exercise prevents the increase of tHcy concentrations and maintains these concentrations at baseline up to 2 h post-exercise. d) Serum tHcy concentrations increased after submaximal exercise when the hydration protocol during exercise was not applied. Furthermore, tHcy concentrations reached maximal values 6 h after the end of exercise. e) At 24 h, tHcy concentrations recovered baseline values independently whether or not there was a hydration protocol during exercise. f) There is a need to clarify the underlying mechanisms related to cardiovascular risk due to the transient increase of tHcy concentrations induced by acute exercise. Further research analayzing the relationship between tHcy concentrations after acute exercise and the implication of creatine, vitamin B12 and folate as related parameters in the homocysteine metabolism is needed. Finally, tHcy concentrations increased above the recommended values after an acute aerobic submaximal exercise; nevertheless, a good hydration protocol maintains tHcy concentrations at baseline and prevents the further increase in a sample of physically active male adults.

The 9-cis-epoxycarotenoid cleavage reaction is the key regulatory step of abscisic acid biosynthesis in water-stressed bean

Abscisic acid (ABA), a cleavage product of carotenoids, is involved in stress responses in plants. A well known response of plants to water stress is accumulation of ABA, which is caused by de novo synthesis. The limiting step of ABA biosynthesis in plants is presumably the cleavage of 9-cis-epoxycarotenoids, the first committed step of ABA biosynthesis. This step generates the C15 intermediate xanthoxin and C25-apocarotenoids. A cDNA, PvNCED1, was cloned from wilted bean (Phaseolus vulgaris L.) leaves. The 2,398-bp full-length PvNCED1 has an ORF of 615 aa and encodes a 68-kDa protein. The PvNCED1 protein is imported into chloroplasts, where it is associated with the thylakoids. The recombinant protein PvNCED1 catalyzes the cleavage of 9-cis-violaxanthin and 9′-cis-neoxanthin, so that the enzyme is referred to as 9-cis-epoxycarotenoid dioxygenase. When detached bean leaves were water stressed, ABA accumulation was preceded by large increases in PvNCED1 mRNA and protein levels. Conversely, rehydration of stressed leaves caused a rapid decrease in PvNCED1 mRNA, protein, and ABA levels. In bean roots, a similar correlation among PvNCED1 mRNA, protein, and ABA levels was observed. However, the ABA content was much less than in leaves, presumably because of the much smaller carotenoid precursor pool in roots than in leaves. At 7°C, PvNCED1 mRNA and ABA were slowly induced by water stress, but, at 2°C, neither accumulated. The results provide evidence that drought-induced ABA biosynthesis is regulated by the 9-cis-epoxycarotenoid cleavage reaction and that this reaction takes place in the thylakoids, where the carotenoid substrate is located.

Muramic lactam in peptidoglycan of Bacillus subtilis spores is required for spore outgrowth but not for spore dehydration or heat resistance

Bacterial endospores derive much of their longevity and resistance properties from the relative dehydration of their protoplasts. The spore cortex, a peptidoglycan structure surrounding the protoplasm, maintains, and is postulated to have a role in attaining, protoplast dehydration. A structural modification unique to the spore cortex is the removal of all or part of the peptide side chains from the majority of the muramic acid residues and the conversion of 50% of the muramic acid to muramic lactam. A mutation in the cwlD gene of Bacillus subtilis, predicted to encode a muramoyl-l-alanine amidase, results in the production of spores containing no muramic lactam. These spores have normally dehydrated protoplasts but are unable to complete the germination/outgrowth process to produce viable cells. Addition of germinants resulted in the triggering of germination with loss of spore refractility and the release of dipicolinic acid but no degradation of cortex peptidoglycan. Germination in the presence of lysozyme allowed the cwlD spores to produce viable cells and showed that they have normal heat resistance properties. These results (i) suggest that a mechanical activity of the cortex peptidoglycan is not required for the generation of protoplast dehydration but rather that it simply serves as a static structure to maintain dehydration, (ii) demonstrate that degradation of cortex peptidoglycan is not required for spore solute release or partial spore core rehydration during germination, (iii) indicate that muramic lactam is a major specificity determinant of germination lytic enzymes, and (iv) suggest the mechanism by which the spore cortex is degraded during germination while the germ cell wall is left intact.

Antioxidative Defense System, Pigment Composition, and Photosynthetic Efficiency in Two Wheat Cultivars Subjected to Drought1

We analyzed antioxidative defenses, photosynthesis, and pigments (especially xanthophyll-cycle components) in two wheat (Triticum durum Desf.) cultivars, Adamello and Ofanto, during dehydration and rehydration to determine the difference in their sensitivities to drought and to elucidate the role of different protective mechanisms against oxidative stress. Drought caused a more pronounced inhibition in growth and photosynthetic rates in the more sensitive cv Adamello compared with the relatively tolerant cv Ofanto. During dehydration the glutathione content decreased in both wheat cultivars, but only cv Adamello showed a significant increase in glutathione reductase and hydrogen peroxide-glutathione peroxidase activities. The activation states of two sulfhydryl-containing chloroplast enzymes, NADP+-dependent glyceraldehyde-3-phosphate dehydrogenase and fructose-1,6-bisphosphatase, were maintained at control levels during dehydration and rehydration in both cultivars. This indicates that the defense systems involved are efficient in the protection of sulfhydryl groups against oxidation. Drought did not cause significant effects on lipid peroxidation. Upon dehydration, a decline in chlorophyll a, lutein, neoxanthin, and β-carotene contents, and an increase in the pool of de-epoxidized xanthophyll-cycle components (i.e. zeaxanthin and antheraxanthin), were evident only in cv Adamello. Accordingly, after exposure to drought, cv Adamello showed a larger reduction in the actual photosystem II photochemical efficiency and a higher increase in nonradiative energy dissipation than cv Ofanto. Although differences in zeaxanthin content were not sufficient to explain the difference in drought tolerance between the two cultivars, zeaxanthin formation may be relevant in avoiding irreversible damage to photosystem II in the more sensitive cultivar.

A Gene Encoding Proline Dehydrogenase Is Not Only Induced by Proline and Hypoosmolarity, but Is Also Developmentally Regulated in the Reproductive Organs of Arabidopsis1

The cDNA clone ERD5 (early responsive to dehydration), isolated from 1-h-dehydrated Arabidopsis, encodes a precursor of proline (Pro) dehydrogenase (ProDH), which is a mitochondrial enzyme involved in the first step of the conversion of Pro to glutamic acid. The transcript of the erd5 (ProDH) gene was undetectable when plants were dehydrated, but large amounts of transcript accumulated when plants were subsequently rehydrated. Accumulation of the transcript was also observed in plants that had been incubated under hypoosmotic conditions in media that contained l- or d-Pro. We isolated a 1.4-kb DNA fragment of the putative promoter region of the ProDH gene. The β-glucuronidase (GUS) reporter gene driven by the 1.4-kb ProDH promoter was induced not only by rehydration but also by hypoosmolarity and l- and d-Pro at significant levels in transgenic Arabidopsis plants. The promoter of the ProDH gene directs strong GUS activity in reproductive organs such as pollen and pistils and in the seeds of the transgenic plants. GUS activity was detected in vegetative tissues such as veins of leaves and root tips when the transgenic plants were exposed to hypoosmolarity and Pro solutions. GUS activity increased during germination of the transgenic plants under hypoosmolarity. The relationship between Pro metabolism and the physiological aspects of stress response and development are discussed.