Conduction and photoelectrochemical properties of monomeric and electropolymerized tetraruthenated porphyrin films.

The influence of the preparation method on the structure, conduction and photoelectrochemical properties of monomeric and polymeric tetraruthenated porphyrin films on ITO glass and nanocrystalline TiO2 has been investigated. The films were characterized by STM, MAC mode SFM, cyclic voltammetry, electrochemical impedance spectroscopy (EIS) and combined electro-/photoelectrochemical techniques. The electronic diffusion coefficient D(e)C(m)2 of the films differed by three to four orders of magnitude depending on the procedure employed for the deposition process. The photoelectrochemical properties were evaluated either: by depositing the films directly on transparent ITO electrodes, under an applied bias potential and presence of O2 as electron acceptor; or by depositing the porphyrin material on nanocrystalline TiO2 in a Gr?tzel-type cell. In the first case the porphyrin films exhibited a typical p-type semiconductor behavior described by a Schottky junction model, while in the second the films behaved as a sensitizer of an n-type semiconductor. The photoelectrochemical properties of the porphyrin films and their performance as sensitizer in Gr?tzel-type cells were found to be strongly dependent on the conductivity and packing characteristics of the material. Semi-empirical calculations were performed by modified MM2 and ZINDO/S methods, in order to simulate the packing and electronic structures of the tetraruthenated porphyrin.     

The emergent role of sarcopenia: Preliminary Report of the Observatory of Sarcopenia of the Spanish Society of Geriatrics and Gerontology

Sarcopenia is a common and prominent geriatric syndrome, of major interest for daily clinical practice of professionals working with older people. The number of affected individuals and its relation with disability, frailty, many chronic diseases, lifestyle and adverse outcomes are extremely relevant for geriatric care. Moreover, biological changes that lead to the loss of muscle mass and strength are intrinsically related to the mechanisms of aging. It is not therefore surprising that research in this field is growing exponentially in recent years, and sarcopenia has been placed in recent years in the forefront of research in geriatric medicine and gerontology. The Spanish Society of Geriatrics and Gerontology has recently created an Observatory of Sarcopenia, which aims to promote educational and research activities in this field. The first activity of the Observatory has been to offer the Spanish speaking scientific community a review of the current status of sarcopenia, that may allow unifying concepts and fostering interest in this promising field of geriatrics.     

La información del diagnóstico en la demencia

Dementia is a syndrome characterized by a progressive deterioration of cognitive functions, accompanied by psychiatric symptoms and behavioral disturbances that produce a progressive and irreversible disability. The way it should communicate the diagnosis of dementia is a key discussion point on which there is no unanimous agreement so far. The communicating of the diagnosis of dementia is a complex issue that affects not only, the patient but also to caregivers and health professionals who care and must conform to the ethical principles governing medical practice (autonomy, nonmaleficence, beneficence, and justice). Therefore, from the Dementia Working Group of the Catalan Geriatric Society (Grupo de Trabajo de Demencia de la Sociedad Catalana de Geriatría) arises the need to review the issue and propose a course of action for the disclosure of diagnosis.     

La eclosión de la sarcopenia: Informe preliminar del Observatorio de la Sarcopenia de la Sociedad Española de Geriatría y Gerontología

Sarcopenia is a common and prominent geriatric syndrome, of major interest for daily clinical practice of professionals working with older people. The number of affected individuals and its relation with disability, frailty, many chronic diseases, lifestyle and adverse outcomes are extremely relevant for geriatric care. Moreover, biological changes that lead to the loss of muscle mass and strength are intrinsically related to the mechanisms of aging. It is not therefore surprising that research in this field is growing exponentially in recent years, and sarcopenia has been placed in recent years in the forefront of research in geriatric medicine and gerontology.The Spanish Society of Geriatrics and Gerontology has recently created an Observatory of Sarcopenia, which aims to promote educational and research activities in this field. The first activity of the Observatory has been to offer the Spanish speaking scientific community a review of the current status of sarcopenia, that may allow unifying concepts and fostering interest in this promising field of geriatrics.     

Bacteriological Properties of a Sucrose-Fermenting Corynebacterium diphtheriae Strain Isolated from a Case of Endocarditis

An atypical sucrose-fermenting Corynebacterium diphtheriae strain was isolated from three blood cultures of a 14-year-old girl presented to a university teaching hospital in Rio de Janeiro, Brazil. She had mitral endocarditis that proved to be fatal despite intensive antibiotic therapy. Blood cultures showed a fluorescent Gram-positive, aerobic, coryneform-like bacillus presenting pyrazinamidase and CAMP reaction negative. The isolate was identified as a toxigenic strain of C. diphtheriae var. mitis by both Elek and radial immunodiffusion (RID) tests. The invasive C. diphtheriae sucrose-fermenting biotype strain adhered to glass surfaces and expressed pronounced hemagglutinating activity (titer 8), a property common among the nonfermenting biotype strains. Laboratories should be alert to the possibility of the isolation of C. diphtheriae with a positive sucrose fermentation test, especially when nontoxigenic strains are isolated from uncommon anatomic sites. Received: 24 November 1997 / Accepted: 5 March 1998     

Lupus eritematoso sistémico en el anciano

Late-onset systemic lupus erythematosus (SLE) usually appears in patients older than 65 years and has clinical features different from the classical form observed in younger patients. In the elderly, SLE represents 10-20% of all SLE cases, shows a different and less aggressive clinical evolution and the first manifestations are non-specific. A significantly higher incidence of late-onset SLE in males, and the fact that postmenopausal women have a more benign disease, suggests that the estrogenic status may influence the activity of the disease. Owing to the insidious onset and the non-specific clinical manifestations on presentation, there is commonly a delayed diagnosis of late-onset SLE. Furthermore, the presence of comorbidities and concomitant therapies in elderly patients may limit the therapeutic options for SLE. The treatment of choice of joint symptoms and serositis includes non-steroidal anti-inflammatory drugs and low-dose steroids for short periods. In addition to the need for adopting a multidisciplinary approach, it is fundamental to obtain information about the functional, cognitive and social status of these patients in order to make appropriate healthcare decisions.     

Cell surface components and adhesion in Corynebacterium diphtheriae

Main primary approaches and new developments in the study of the molecular basis of the adhesive process of Corynebacterium diphtheriae are reviewed along with a discussion of the potential importance of hemagglutinins, exposed sugar residues, hydrophobins and trans-sialidase enzymes as adhesins of strains of the sucrose fermenting and non-fermenting biotypes.     

Eimeria saudiensis N. Sp. (Apicomplexa: Eimeriidae) from the Arabian Oryx (Oryx leucoryx) in Saudi Arabia

Oocysts of Eimeria saudiensis n. sp. (Apicomplexa: Eimeriidae) are described from the feces of the Arabian oryx, Oryx leucoryx , from the Riyadh Zoo, Saudi Arabia. The oocysts were ellipsoidal or slightly ovoid, 31.2 times 24.5 (24.3–36.5 times 20.0–27.6) μm with a bilayered wall about 1.7 μm thick. The micropyle was covered by a dome-shaped cap. The oocyst residuum was absent, but tiny polar granules were present. The sporocysts were elongate ovoid, 14.3 times 7.2 (11.5–18.5 times 6.0–9.0) μm, had a Stieda body, but lacked a substiedal body. The sporocyst residuum was present, composed of numerous small granules. The sporozoites were elongate club-shaped, and contained two prominent refractile bodies.