Dealloyed Ruthenium Film Catalysts for Hydrogen Generation from Chemical Hydrides.

Thin-film ruthenium (Ru) and copper (Cu) binary alloys have been prepared on a Teflon™ backing layer by cosputtering of the precious and nonprecious metals, respectively. Alloys were then selectively dealloyed by sulfuric acid as an etchant, and their hydrogen generation catalysts performances were evaluated. Sputtering time and power of Cu atoms have been varied in order to tailor the hydrogen generation performances. Similarly, dealloying time and the sulfuric acid concentration have also been altered to tune the morphologies of the resulted films. A maximum hydrogen generation rate of 35 mL min-1 was achieved when Cu sputtering power and time were 200 W and 60 min and while acid concentration and dealloying time were 18 M and 90 min, respectively. It has also been demonstrated that the Ru content in the alloy after dealloying gradually increased with the increasing the sputtering power of Cu. After 90 min dealloying, the Ru to Cu ratio increased to about 190 times that of bare alloy. This is the key issue for observing higher catalytic activity. Interestingly, we have also presented template-free nanoforest-like structure formation within the context of one-step alloying and dealloying used in this study. Last but not least, the long-time hydrogen generation performances of the catalysts system have also been evaluated along 3600 min. During the first 600 min, the catalytic activity was quite stable, while about 24% of the catalytic activity decayed after 3000 min, which still makes these systems available for the development of robust catalyst systems in the area of hydrogen generation.

[Clinical pathways: bases, description and potential uses in neurology]. / Vías clínicas: fundamentos, descripción y posibles aplicaciones en Neurología.

Over the last 10 years, we have witnessed the introduction of different procedures for coordinating clinical care, often shown as new tools in the hospital administration setting. Clinical or critical pathways are among these standardization methods of health care. In this article, we describe the characteristics of the clinical pathways and review their potential uses in neurology, especially in common conditions like stroke. In the following, we describe a clinical pathway for treating acute episodes in patients with relapsing-remitting of secondarily progressive forms of multiple sclerosis which was developed in the Son Dureta Hospital, in Palma de Mallorca, Spain. We carry out a critical assessment of this and other standardization methods.

Vías clínicas: fundamentos, descripción y posibles aplicaciones en Neurología / Clinical pathways: bases, description and potential uses in neurology

En los últimos años hemos asistido a la introducción de diferentes sistemas de estandarización en la práctica clínica hospitalaria, presentados como herramientas de ayuda propias de la nueva metodología de gestión de los hospitales públicos como entidades empresariales. Entre estos sistemas de estandarización de la actividad asistencial se encuentran las vías clínicas. En el presente artículo se lleva a cabo una descripción de las vías y se revisan sus posibles aplicaciones en el ámbito de la neurología, con mayor detalle en aquellos procesos más relevantes, como es el caso del ictus. A continuación, se presenta una vía clínica desarrollada en el Hospital Son Dureta de Palma de Mallorca para el tratamiento de los brotes agudos en pacientes con formas remitentes-recidivantes o secundariamente progresivas de esclerosis múltiple. Efectuamos una evaluación crítica de este y otros sistemas de estandarización (AU)

[Early endoscopic findings of the upper respiratory and digestive tract in patients undergoing translaryngeal intubation for more than 24 hours]. / Hallazgos endoscópicos precoces de las vías aerodigestivas superiores en pacientes sometidos a intubación translaríngea de más de veinticuatro horas.

The large number of patients undergoing translaryngeal intubation justifies acquiring full knowledge of the complications that this invasive procedure may produce. The short-term problems that cause immediate complications (esophageal intubation, cuff rupture) are severe and do not escape notice. However, less immediate problems often pass undetected, although their presence may worsen the patient's outcome. Endoscopy allows the condition of the upper respiratory and digestive tract to be examined in order to detect and correct such problems. In this preliminary study, risk factors are analyzed and the lesions are described, classified, and quantified. Forty-seven adult patients were studied prospectively. In the first 24 to 48 hours of intubation, rigid endoscopy was performed under sedation using 0 degree and 30 degrees rigid endoscopes. The high rate of glottic edema (63.8%) was noteworthy because knowledge of this condition can be vital for preventing extubation failure.

Endoscopic evolution of laryngeal injuries caused by translaryngeal intubation.

Despite improvements in tube design and materials, the longer survival rates of critically ill patients make laryngeal and tracheal lesions still common following prolonged translaryngeal intubation. The time of intubation is almost the only factor employed in deciding whether or not tracheotomy has to be performed. Some patients will not develop laryngeal lesions afer long intubation periods, whereas some already have clinical symptoms after short periods of time. If the conditions of the larynx and trachea could be assessed before irreversible complications take place, then timing of tracheotomy could be individualized to avoid laryngeal stenosis as well as unnecessary tracheostomies. We present the preliminary results of an endoscopic study of the early laryngeal changes that take place during translaryngeal intubation. The method of exploration is explained and tissue changes seen and their evolution after extubation are described, emphasizing those that could have a predictive value.

[Prognostic factors in benign intracranial hypertension]. / Factores pronósticos en la hipertensión intracraneal benigna.

The incidence of permanent visual loss in Benign Intracranial Hypertension (BIH) was assessed. 17 out of 100 patients with BIH had permanent visual loss which was severe in only three cases. We tried to identify the risk factors in this group of patients. Statistical analysis showed that the following factors were related with a bad visual outcome: atrophy of the disc, visual loss and field defects (other than enlargement of the blind stop) present at the first exam; delay of treatment; BIH in patients older than 40 years and, overall, presence of systemic hypertension. The identification of this risk factors may help in planning the treatment of the disorder.

[Herpes zoster ophthalmicus with contralateral hemiplegia]. / Herpes zoster oftálmico con hemiplejia contralateral.

A 57-year-old patient nonimmunosuppressed who had zoster ophthalmicus associated to contralateral hemiplegia is presented. We noticed on the CT scan an infarction of left caudate nucleus, as well as in the angiography signs of vasculitis. We comment on the clinical and diagnosis features and suggest possible benefit effects of the treatment with acyclovir.

[Historical and current concept of benign intracranial hypertension]. / Concepto histórico y actual de la hipertensión intracraneal benigna.

The concepts of serous meningitis, pseudotumour cerebri, hypertensive meningeal state and otitic hydrocephalus have not been considered historically as synonyms nor can they be superimposed on what is currently known as Benign Intracranial Hypertension (BIH). BIH is a syndrome of intracranial hypertension with no clinical, radiological or analytical evidence for the existence of focal or general neurological lesions or hydrocephalus, and which has a self-limiting "benign" development. At present, the diagnostic criteria usually accepted are: 1. Symptoms and signs of intracranial hypertension. 2. Absence of focal neurological symptoms and signs. 3. Absence of radiologically verified cerebral lesion. 4. C.S.F. of normal composition and high pressure. The requirement of other criteria for the diagnosis of BIH, such as angiography, to eliminate the possibility of thrombosis of venous sinuses, or continuous monitoring of C.S.F. pressure, is controversial.

Chronic intracranial hypertension secondary to neurobrucellosis.

Chronic intracranial hypertension in the presence of hydrocephalus and/or arachnoiditis is a rare presentation of neurobrucellosis. The present case is exceptional because neither hydrocephalus nor arachnoiditis were present. Brucellosis was diagnosed by serological tests. The patient developed asthenia, anorexia, weight loss, violent headaches, explosive vomiting, bilateral papilloedema, diplopia with paralysis of the abducens nerves, left supranuclear facial paralysis and left hemiparesis. A skull radiograph showed destruction of the sella turcica. Rapid recovery was attained with the use of antibiotics. The pathogenesis of this intracranial hypertension syndrome with destruction of sella turcica is discussed.