Desarrollo de materiales sólidos para captura de CO2 a bajas temperaturas

Una vez comprobado el problema medioambiental existente en nuestro planeta en cuanto a emisiones de gases de efecto invernadero (GEI) y con el objetivo de reducir dichas emisiones, se están desarrollando nuevos métodos y materiales sintéticos para la captura de CO2, entre otros. Este proyecto pretende estudiar una tecnología de captura de CO2, centrándose en el estudio postcombustión basado en materiales sólidos compuestos por sílice impregnados del grupo amino. El método experimental utilizado ha consistido en realizar las síntesis por duplicado de tres materiales diferentes basados en un soporte de sílices impregnadas con aminas diferentes: 3‐aminopropiltrimetoxisilano (APTMS), N‐3‐(trimetoxisil)propil)etano‐1,2‐ diamina) (AEAPTMS) y Polietilenimina (PEI). Estos materiales han sido caracterizados mediante las técnicas experimentales: Análisis de área superficial BET, pH, Análisis Termogravimétrico, Análisis Elemental y Microscopia Electrónica de Barrido (MEB). El estudio para evaluar la captura de CO2, se ha realizado mediante la Balanza de Suspensión Magnética en condiciones de presión atmosférica y bajas temperaturas (45‐105ºC). Con un 10 vol. % CO2 en N2 a 45ºC para la absorción CO2 y a 105ºC para la desorción. La capacidad de captura de CO2 para los materiales estudiados se sitúa entorno a un 3%, que difiere considerablemente de los estudios publicados en la bibliografía. En contrapartida el comportamiento de los materiales sometidos al proceso de captura de CO2 es constante, ya que perdura a lo largo de los ciclos, y reversible debido a la práctica totalidad de absorción y desorción de masa en este proceso.

Stroke Aphasia: 1,500 Consecutive Cases.

Background: To study the characteristics of vascular aphasia in a cohort of patients with a first-ever stroke. Methods: All patients admitted to the Lausanne neurology department for a first-ever stroke between 1979 and 2004 were included. Neurological examination including language was performed on admission. Stroke risk factors, stroke origin and location, associated symptoms and Rankin scale scores were recorded for each patient. The influence of these factors on aphasia frequency and subtypes was analyzed using logistic regression models. Results: 1,541 (26%) of patients included in this study had aphasia. The more frequent clinical presentations were expressive-receptive aphasia (38%) and mainly expressive aphasia (37%), whereas mainly receptive aphasia was less frequently observed (25%). In ischemic stroke, the frequency of aphasia increased with age (55% of nonaphasic vs. 61% of aphasic patients were more than 65 years old), female sex (40% of women in the nonaphasia group vs. 44% in the aphasia group) and risk factors for cardioembolic origin (coronary heart disease 20 vs. 26% and atrial fibrillation 15 vs. 24%). Stroke aphasia was more likely associated with superficial middle cerebral artery (MCA) stroke and leads to relevant disability. Clinical subtypes depended on stroke location and associated symptoms. Exceptions to the classic clinical-topographic correlations were not rare (26%). Finally, significant differences were found for patients with crossed aphasia in terms of stroke origin and aphasia subtypes. Conclusions: Risk factors for stroke aphasia are age, cardioembolic origin and superficial MCA stroke. Exceptions to classic clinical-topographic correlations are not rare. Stroke aphasia is associated with relevant disability. Stroke location and associated symptoms strongly influence aphasia subtypes.

Avaluació de la qualitat de vida dels pacients amb tumor vesical sotmesos a tractament amb BCG o Mitomicina endovesical

El tumor vesical superficial és la neoplàsia més comuna de l’aparell genitourinari. El tractament d’elecció és la RTU vesical, però moltes vegades precisa d’adjuvància posterior, com les instil•lacions de BCG o Mitomicina C endovesicals. Aquests tractaments no estan exempts d’efectes adversos, que poden afectar la qualitat de vida dels pacients als quals se’ls administra. La qualitat de vida relacionada amb la salut és una eina important per valorar l’impacte que tenen alguns procediments terapèutics. Mitjançant qüestionaris de salut es pretén avaluar-ho. S’ha intentat crear un qüestionari que pugui utilitzar-se en la pràctica diària pels pacients que reben tractament amb quimioteràpia o immunoteràpia endovesical.

Descripción socioambiental y análisis de las fuentes de agua de la microcuenca La Jabonera (Estelí, Nicaragua)

El objetivo principal de este proyecto es la caracterización de la microcuenca la Jabonera (Estelí, Nicaragua) enfatizando el agua como factor clave que conecta todos los elementos que interaccionan en la microcuenca y que, además delimita el área de estudio. El trabajo de campo ha consistido básicamente en la georeferenciación de los puntos de interés, la realización de encuestas a la población y la evaluación de las fuentes de agua y del agua del río mediante análisis fisicoquímicos. En el procesamiento de la información se ha elaborado cartografía temática mediante la herramienta SIG que ha servido de soporte para la interpretación de los resultados. Las características morfométricas y biofísicas favorecen que el agua precipitada se pierda rápidamente por escorrentía superficial con una tendencia moderada a crecidas e inundaciones. El agua infiltrada circula rápidamente por fracturas del material geológico con tiempos de tránsito cortos, y además, el área de recarga de los nacientes es local por lo que las fuentes son especialmente vulnerables a períodos de sequía y a la contaminación en su entorno cercano. El estudio de usos del suelo junto con la realización de análisis del agua ha permitido determinar que los agroquímicos son la principal fuente potencial de contaminación del agua en la microcuenca. Los resultados obtenidos muestran la necesidad de llevar a cabo una gestión integrada del territorio que garantice un desarrollo socioambiental sostenible.

Life-threatening versus non-life-threatening manual strangulation: are there appropriate criteria for MR imaging of the neck?

The aim of the study was to determine objective radiological signs of danger to life in survivors of manual strangulation and to establish a radiological scoring system for the differentiation between life-threatening and non-life-threatening strangulation by dividing the cross section of the neck into three zones (superficial, middle and deep zone). Forensic pathologists classified 56 survivors of strangulation into life-threatening and non-life-threatening cases by history and clinical examination alone, and two blinded radiologists evaluated the MRIs of the neck. In 15 cases, strangulation was life-threatening (27%), compared with 41 cases in which strangulation was non-life-threatening (73%). The best radiological signs on MRI to differentiate between the two groups were intramuscular haemorrhage/oedema, swelling of platysma and intracutaneous bleeding (all p = 0.02) followed by subcutaneous bleeding (p = 0.034) and haemorrhagic lymph nodes (p = 0.04), all indicating life-threatening strangulation. The radiological scoring system showed a sensitivity and specificity of approximately 70% for life-threatening strangulation, when at least two neck zones were affected. MRI is not only helpful in assessing the severity of strangulation, but is also an excellent documentation tool that is even admissible in court.

Copper filtration in pediatric digital X-ray imaging: its impact on image quality and dose.

The effect of copper (Cu) filtration on image quality and dose in different digital X-ray systems was investigated. Two computed radiography systems and one digital radiography detector were used. Three different polymethylmethacrylate blocks simulated the pediatric body. The effect of Cu filters of 0.1, 0.2, and 0.3 mm thickness on the entrance surface dose (ESD) and the corresponding effective doses (EDs) were measured at tube voltages of 60, 66, and 73 kV. Image quality was evaluated in a contrast-detail phantom with an automated analyzer software. Cu filters of 0.1, 0.2, and 0.3 mm thickness decreased the ESD by 25-32%, 32-39%, and 40-44%, respectively, the ranges depending on the respective tube voltages. There was no consistent decline in image quality due to increasing Cu filtration. The estimated ED of anterior-posterior (AP) chest projections was reduced by up to 23%. No relevant reduction in the ED was noted in AP radiographs of the abdomen and pelvis or in posterior-anterior radiographs of the chest. Cu filtration reduces the ESD, but generally does not reduce the effective dose. Cu filters can help protect radiosensitive superficial organs, such as the mammary glands in AP chest projections.

Riesgo aumentado del desarrollo de un segundo melanoma cutáneo primario sobre un nevo en pacientes diagnosticados previamente de melanoma cutáneo primario sobre nevo.

Es van analitzar les característiques de 981 malalts diagnosticats de melanoma cutani, dels quals 47 havien desenvolupat un segon melanoma. L'edat inferior a 40 anys, la localització en el tronc i el subtipus histològic d'extensió superficial, van ser factors de risc independents per al desenvolupament d'un primer melanoma sobre nevo. L'únic factor que es va associar al desenvolupament d'un segon melanoma sobre nevo, va ser que el primer també haguera mostrat esta associació. Estes troballes recalquen la importància preventiva de la vigilància dels nevos en malalts amb melanoma, sobretot quan este es desenvolupa sobre un nevo.

Supervisió i control de la lectura: anàlisi de procediments, judicis metacognitius i resultats de comprensió en estudiants d'Educació Secundària Obligatòria

Els processos de comprensió lectora són complexes, i requereixen de l’ús autorregulat, conscient i deliberat de la metacognició en les seves dues vessants: supervisió i control. L’objectiu d’aquest projecte és analitzar les relacions entre aquests dos components, i la seva repercussió en la comprensió lectora que finalment s’assoleix. Per tal de tractar aquesta qüestió s’han analitzat els processos de lectura seguits per 60 alumnes d’Educació Secundària Obligatòria. La presència i el tipus de relectura ha estat considerada com a mesura de control (estratègia emprada per millorar la pròpia comprensió), mentre que els judicis metacognitius són considerats com a mesura de supervisió. També es va elaborar una prova de comprensió lectora incloent preguntes que requerissin diferents nivells de processament cognitiu, de més superficial a més profund. Els nostres resultats preliminars mostren una relació entre l’ajust dels judicis metacognitius i la comprensió lectora assolida; els lectors que millor entenen el text tendeixen a ser els que millor supervisen la seva comprensió. La relectura també s’ha mostrat útil per millorar la comprensió, ja que els participants obtenen millors resultats després de rellegir. Per últim, s’ha trobat una relació significativa entre l’ajust dels judicis metacognitius i la relectura. D’una banda, aquests resultats subratllen la importància de la supervisió i el control en la comprensió lectora, i ofereixen evidències per explicar les complexes relacions entre supervisió, control, i resultats de comprensió. A més, els processos de lectura i els objectius amb què hom rellegeix apareixen com a temes rellevants que requereixen ser investigats per comprendre millor la interacció entre els processos de supervisió i control en la comprensió lectora. D’altra banda, els resultats tenen valuoses implicacions educatives, ja que proporcionen evidències de la importància d’ensenyar processos metacognitius des d’un punt de vista estratègic, en contraposició a les “tècniques”, per tal de millorar la comprensió lectora.

Clinical and mycological study of scalp white piedra in the State of Paraíba, Brazil

White piedra is a superficial mycoses characterized by nodules on the hair shaft, caused by the basidiomycetous yeasts. In the present study, clinical and mycological findings of scalp white piedra caused by Trichosporon spp. are related. Twenty three cases of scalp white piedra were observed with a high incidence in women (87%) and preschool children from 2 to 6 (74%) years old. These groups presented a relationship of dependence with this infection. Despite the low socio-economic status, poor standards of hygiene, (48% of the patients) as well as the fact that 30.4% of the children shared the same nursery, these factors were not significant for the transmission of the mycosis. These were the first reports of scalp white piedra in João Pessoa city, Paraíba, Brazil.

GDAP1-related autosomal dominant Charcot-Marie-Tooth disease: phenotypical and MRI features

El present estudi es basa en la descripció de quatre famílies portadores d’una mateixa mutació puntual (p.R120W) en el gen GDAP1 que segreguen d’una manera autosòmica dominant. Les trobades més rellevants foren:  Els individus afectats varen tindre un començament més tardà i un fenotipus més lleu que les mutacions recessives del gen GDAP-1, però amb una gran variabilitat clínica.  La Resonància Magnètica Muscular va demostrar una afectació selectiva de la musculatura intrínseca del peu i la part distal del panxell. El compartiment posterior superficial de la musculatura del panxell estava més afectat que el compartiment anterolateral.

Ultrastructural study of the in vitro interaction between Biomphalaria glabrata hemocytes and Schistosoma mansoni miracidia

Biomphalaria glabrata and Schistosoma mansoni relationship was studied by light microscopy (LM) and freeze-fracture replica technique (FFR). We observed very thin cytoplasmic extensions of hemocytes in the LM, which then surround immobilize the miracidia. FFR images showed that the contact site between hemocytes cytoplasmic extensions and the external tegumentary coat involved only superficial layers of miracidia. Numerous vacuoles and filopodia were observed in the hemocyte cytoplasm, the latter binding with those from neighboring cells. In spite of the close interfilopodia contact, no cellular junctions were seen at these sites nor between filopodia-miracidia contact areas. The observed migration of hemocytes and their disposition in layers surrounding the miracidia in vitro correspond to previous studies.

Corneal Opacities in Trisomy 8 Mosaic Syndrome : Clinical, Histologic and Genetic Features

Purpose: To describe the clinical, histologic and genetic findings of corneal opacities in the trisomy 8 mosaic syndrome. Methods: 3 children aged 8 years (Patients A), 6 years (Patients B) and 1 month (Patients C) respectively, were referred with corneal opacities for ophthalmologic evaluation. The 2 older patients had been previously diagnosed with trisomy 8 mosaicism, while the third was diagnosed after the ocular examination. Automated lamellar keratoplasty (ALTK) was performed on the most amblyopic eye. Histopathologic analysis with immunohistochemical markers and cytogenetic studies by FISH using haploid probes for chromosome 8 and chromosome 16 (control) were performed on the excised corneal lesion. Results: All patients presented vascularized corneal opacities involving the superficial stroma, and amblyopia with a bilateral involvement in two of them (Patients A and B). Post-operative follow-up (range 6-20 months) was satisfactory, with the graft remaining clear and improved visual acuity, allowing iso-acuity and stereoscopy in the one month old child (Patients C). The clinically observed corneal opacities corresponded histopathologically to the replacement of the normal anterior corneal stroma by a choristomatous loose richly vascularized connective tissue containing mucopolysacharides. Bowman's membrane was absent. There were no adnexal structures. The overlaying epithelium expressed keratin 3 in all three cases. Keratin 19 was found in the suprabasal epithelial cells in one case but was absent in the other cases. There were no expression of keratin 7 and 1 as well as MUC5AC in the epithelial cells. FISH analysis from 100 interphase cells of the affected tissue and normal conjontival probe revealed normal diploid cells. Conclusions: In this series, the corneal opacities associated with trisomy 8 mosaic syndrome share a common clinical, histopathological and genetic features. ALTK should be considered at diagnosis to prevent amblyopia in these children.

MDCT imaging of calcinosis in systemic sclerosis.

Calcinosis is a typical feature of systemic sclerosis (SSc) and can be found in many different tissues including the superficial soft tissues, periarticular structures, muscles, and tendons. It can also provoke erosive changes on bones. Investigation is conducted most often with plain radiographs. However, when a more detailed assessment is necessary, multidetector computed tomography (MDCT) is helpful owing to its multiplanar reformat (MPR) ability. The purpose of this review is to provide an overview of the various appearances of calcinosis in SSc patients as visualized at MDCT.

Evaluation of a PCR-RFLP assay for the identification of dermatophytes in situ

Dermatophytes are the main cause of superficial mycoses. These fungi have the capacity to invade keratinized tissue of humans or animals to produce infections that are generally restricted to the corneocytes of the skin, hair, and nails. Nevertheless, it is common to obtain negative results from fungal cultures of dermatological specimens where direct mycological examination showed fungal elements (30-40%). However, correct identification of the isolated dermatophytes from Tinea is important to choose the appropriate treatment. Therefore, we aim to develop a rapid polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay based on 28S rDNA that is able to identify dermatophytes species in positive dermatological samples. PCR-RFLP identification of dermatophytes in skin or hair allowed validation of the results obtained in culture. It was also possible to identify the infectious dermatophytes when direct hair/ skin mycological examination showed fungal elements, but negative results were obtained from fungal culture. As a conclusion, PCR methods may provide significant benefits in the rapid diagnosis of Tinea. First, there is an increase in sensitivity of dermatophytes identification when enough material is available. Secondly, identification of the infecting agent can be obtained in 24 hours with PCR-RFLP or sequencing, whereas results from fungal cultures can take 2-3 weeks.

Expression of smoothelin and smooth muscle actin in the skin.

INTRODUCTION: Smoothelin is a cytoskeletal protein of differentiated smooth muscle cells with contractile capacity, distinguishing it from other smooth muscle proteins, such as smooth muscle actin (SMA). OBJECTIVE: To evaluate the expression of smoothelin and SMA in the skin in order to establish specific localizations of smoothelin in smooth muscle cells with high contractile capacity and in the epithelial component of cutaneous adnexal structures. Methods: Immunohistochemical analysis (smoothelin and SMA) was performed in 18 patients with normal skin. RESULTS: SMA was expressed by the vascular structures of superficial, deep, intermediate and adventitial plexuses, whereas smoothelin was specifically expressed in the cytoplasm of smooth muscle cells of the deepest vascular plexus and in no other plexus of the dermis. The hair erector muscle showed intense expression of smoothelin and SMA. Cells with nuclear expression of smoothelin and cytoplasmic expression of SMA were observed in the outer root sheath of the inferior portion of the hair follicles and intense cytoplasmic expression in cells of the dermal sheath to SMA. CONCLUSIONS: We report the first study of smoothelin expression in normal skin, which differentiates the superficial vascular plexus from the deep. The deep plexus comprises vessels with high contractile capacity, which is important for understanding dermal hemodynamics in normal skin and pathological processes. We suggest that the function of smoothelin in the outer root sheath may be to enhance the function of SMA, which has been related to mechanical stress. Smoothelin has not been studied in cutaneous pathology; however we believe it may be a marker specific for the diagnosis of leiomyomas and leiomyosarcomas of the skin. Also, smoothelin could differentiate arteriovenous malformations of cavernous hemangioma of the skin