Antimicrobial Photodynamic Polymeric Films Bearing Biscarbazol Triphenylamine End-Capped Dendrimeric Zn(II) Porphyrin.

A novel biscarbazol triphenylamine end-capped dendrimeric zinc(II) porphyrin (DP 5) was synthesized by click chemistry. This compound is a cruciform dendrimer that bears a nucleus of zinc(II) tetrapyrrolic macrocycle substituted at the meso positions by four identical substituents. These are formed by a tetrafluorophenyl group that possesses a triazole unit in the para position. This nitrogenous heterocyclic is connected to a 4,4'-di(N-carbazolyl)triphenylamine group by means of a phenylenevinylene bridge, which allows the conjugation between the nucleus and this external electropolymerizable carbazoyl group. In this structure, dendrimeric arms act as light-harvesting antennas, increasing the absorption of blue light, and as electroactive moieties. The electrochemical oxidation of the carbazole groups contained in the terminal arms of the DP 5 was used to obtain novel, stable, and reproducible fully π-conjugated photoactive polymeric films (FDP 5). First, the spectroscopic characteristics and photodynamic properties of DP 5 were compared with its constitutional components derived of porphyrin P 6 and carbazole D 7 moieties in solution. The fluorescence emissions of the dendrimeric units in DP 5 were more strongly quenched by the tetrapyrrolic macrocycle, indicating photoinduced energy transfer. In addition, FDP 5 film showed the Soret and Q absorption bands and red fluorescence emission of the corresponding zinc(II) porphyrin. Also, FDP 5 film was highly stable to photobleaching, and it was able to produce singlet molecular oxygen in both N,N-dimethylformamide (DMF) and water. Therefore, the porphyrin units embedded in the polymeric matrix of FDP 5 film mainly retain the photochemical properties. Photodynamic inactivation mediated by FDP 5 film was investigated in Staphylococcus aureus and Escherichia coli. When a cell suspension was deposited on the surface, complete eradication of S. aureus and a 99% reduction in E. coli survival were found after 15 and 30 min of irradiation, respectively. Also, FDP 5 film was highly effective to eliminate individual bacteria attached to the surface. In addition, photodynamic inactivation (PDI) sensitized by FDP 5 film produced >99.99% bacterial killing in biofilms formed on the surface after 60 min irradiation. The results indicate that FDP 5 film represents an interesting and versatile photodynamic active material to eradicate bacteria as planktonic cells, individual attached microbes, or biofilms.

The tumor antigen N-glycolyl-GM3 is a human CD1d ligand capable of mediating B cell and natural killer T cell interaction.

The expression of N-glycolyl-monosialodihexosyl-ganglioside (NGcGM3) in humans is restricted to cancer cells; therefore, it is a tumor antigen. There are measurable quantities of circulating anti-NGcGM3 antibodies (aNGcGM3 Abs) in human serum. Interestingly, some people have circulating Ag-specific immunoglobulins G (IgGs) that are capable of complement mediated cytotoxicity against NGcGM3 positive cells, which is relevant for tumor surveillance. In light of the chemical nature of Ag, we postulated it as a candidate ligand for CD1d. Furthermore, we hypothesize that the immune mechanism involved in the generation of these Abs entails cross talk between B lymphocytes (Bc) and invariant natural killer T cells (iNKT). Combining cellular techniques, such as flow cytometry and biochemical assays, we demonstrated that CD1d binds to NGcGM3 and that human Bc present NGcGM3 in a CD1d context according to two alternative strategies. We also showed that paraformaldehyde treatment of cells expressing CD1d affects the presentation. Finally, by co-culturing primary human Bc with iNKT and measuring Ki-67 expression, we detected a reproducible increment in the proliferation of the iNKT population when Ag was on the medium. Our findings identify a novel, endogenous, human CD1d ligand, which is sufficiently competent to stimulate iNKT. We postulate that CD1d-restricted Bc presentation of NGcGM3 drives effective iNKT activation, an immunological mechanism that has not been previously described for humans, which may contribute to understanding aNGcGM3 occurrence.

Human memory B cells isolated from blood and tonsils are functionally distinctive.

Human B-cell studies in vitro have routinely used B lymphocytes purified from spleen, blood or tonsils irrespective of potential differences in their immunological traits. In this study, we compared the functional responses of total (CD19(+)) and memory B cells (Bmem; CD19(+)/CD27(+)) isolated from blood and tonsils to different stimuli. Peripheral B cells showed enhanced survival and proliferation compared with their tonsillar equivalents when stimulated for 10 days. Stimulated B cells from both tissues secreted significantly greater amounts of cytokines than unstimulated controls demonstrating their functional responsiveness. Analysis of CD27 expression over time indicated that the conditions that promoted survival and proliferation of peripheral Bmem, caused massive tonsillar Bmem death. Purified tonsillar Bmem failed to expand but rapidly differentiated in antibody secreting cells and subsequently underwent apoptosis. In contrast, circulating Bmem showed delayed activation and differentiation, but exhibited a longer lifespan and active proliferation. In addition, short-term stimulation of tonsillar Bmem resulted in the production of more immunoglobulin G (IgG) than their peripheral counterparts. At later time points, however, IgG production from the different B cells was reversed. Our findings imply that the tissue located and peripheral Bmem have distinct behaviors, indicating organ dependent functional responses that should not be generalizable to all Bmem. This work provides a greater understanding of how Bmem location is coupled to specialized roles of B lymphocytes.

Análisis psicométrico de la escala multidimensional de autoconcepto AF5 en una muestra de adolescentes y adultos de Cataluña / Psychometric analysis of the AF5 multidimensional scale of self-concept in a sample of adolescents and adults in Catalonia

El objetivo del presente estudio es realizar un análisis psicométrico de la escala AF5 en una muestra catalana de 4.825 sujetos de 11 a 63 años, estudiantes de ESO, bachillerato, ciclos formativos de grado medio (CFGM) y universitarios. Mediante un análisis de componentes principales (ACP) se constata la validez teórica de los componentes y se analiza la fiabilidad del instrumento. Se realizan análisis diferenciales por género y grupo normativo utilizando un diseño factorial 2x6. La variable grupo normativo incluye diferentes cursos en 6 subgrupos: universitarios, Post-ESO (estudiantes de bachillerato y CFGM), 4º Eso, 3º ESO, 2º ESO y 1º ESO. Los resultados indican que la fiabilidad de la versión catalana de la escala es similar a la de la escala original. También la estructura factorial coincide con la del modelo original establecido a priori. Se observan diferencias significativas por grupo normativo en los cuatro componentes del autoconcepto explorados (social, familiar, académico/laboral y físico). Por razón de género, las diferencias significativas aparecen en los componentes del autoconcepto físico, académico y social pero no en el familiar (AU)

The aim of this study is to carry out a psychometric study of the AF5 scale in a sample of 4.825 Catalan subjects from 11 to 63 years-old. They are students from secondary compulsory education (ESO), from high school, middle-level vocational training (CFGM) and from the university. Using a principal component analysis (PCA) the theoretical validity of the components is established and the reliability of the instrument is also analyzed. Differential analyses are performed by gender and normative group using a 2x6 factorial design. The normative group variable includes the different levels classified into 6 sub-groups: university, post-compulsory secondary education (high school and CFGM), 4th of ESO, 3rd of ESO, 2nd of ESO and 1st of ESO. The results indicate that the reliability of the Catalan version of the scale is similar to the original scale. The factorial structure also fits with the original model established beforehand. Significant differences by normative group in the four components of self-concept explored (social, family, academic/occupational and physical) are observed. By gender, significant differences appear in the component of physical self-concept, academic and social but not in the family component (AU)

Patrones de consumo de alcohol en la adolescencia / Alcohol consumption patterns in adolescence

Este estudio analiza los patrones de consumo de alcohol y el papel de la influencia social y la percepción de peligrosidad de esta sustancia en dicho consumo en una muestra de 1.624 estudiantes de Secundaria de Girona con edades comprendidas entre los 12 y los 18 años (49,4% chicos). Los resultados muestran que un 20,9% de los adolescentes se consideran consumidores habituales de alcohol, y que el consumo se incrementa con la edad, independientemente del género. Un porcentaje elevado de consumidores supera el umbral de alto riesgo para la salud, principalmente entre las chicas debido a las diferencias de género en la metabolización alcohólica. Asimismo se confirma la influencia del entorno (amigos y familiares) y de la percepción de peligrosidad del alcohol tanto en el consumo de esta sustancia como en su uso de alto riesgo(AU)

This study analyses alcohol consumption patterns and the role of social influence and risk perception of this substance on its consumption, in a sample of 1,624 secondary school students from Girona aged between 12 and 18 years (49.4% boys). The results show that 20.9% of the teenagers consider themselves regular alcohol consumers and that consumption increases with age, regardless of gender. A high percentage of consumers overcomes the high-risk health threshold, mainly amongst girls because of the gender differences in the metabolism of alcohol. Moreover, the influence of the social environment (friends and family) and risk perception of alcohol both on consumption and high-risk consumption is confirmed(AU)

[Adolescent use of helmets moped riders in the city of Gerona, Spain, 2006]. / Uso del casco en adolescentes usuarios de ciclomotores en la ciudad de Gerona, 2006.

BACKGROUND: Cerebral injuries as a result of craniocerebral trauma are the most frequent cause of death in traffic collisions involving two-wheeled vehicles. In spite of the proven effectiveness of the use of the head protective devices to prevent injuries in the event of traffic collisions, some teenagers and youngsters do not use it. The main goal of this research is to identify the best predictors of helmet use among adolescents. METHOD: Transversal study of a population of 874 young students of Secondary Education during the academic year 2005-06. The population object of study were students of 3rd and 4th year of the 6 public secondary schools of Gerona and only those present in class in the day of the data capture participated in the study. The participation was 74.6%. The data capture was carried out by means of a self-devised survey. An analysis of hierarchical logistical regression was also carried out. RESULTS: Predictable variables of helmet use in motorcycle drivers: age (OR=0.56), safety as main reason for its use (OR=0.02), possession of driving license (OR=0.17), peer influence (OR=0.23) and family influence (OR=0.17). In passengers: age (OR=0.46), peer influence (OR=0.35) and safety as main reason for its use (OR=0.38). CONCLUSIONS: The variables that predict the use of the helmet in the motorcycles users are: age, being in possession of the license to drive motorcycles, wearing the helmet as a safety device and social reinforcement (friends and family).

[Global respiratory failure as the presentation form of hypothyroidism. Report of one case]. / Insuficiencia respiratoria global como forma de presentación de un hipotiroidismo. Comunicación de un caso.

We report a 36 years male, admitted to the hospital for progressive respiratory failure. Chest X ray and CT scan were normal. On admission, a severe bradycardia and slow intellectual activity were noted. Serum thyroid function tests showed a TSH over 150 microU/ml and T3 of 75 ng/ml. Thyroid substitution therapy was associated with a progressive improvement of respiratory function. Diaphragmatic dysfunction, central hypoventilation, airway obstruction, sleep apnea and pleural effusion have been previously reported in patients with hypothyroidism. Therefore, we recommend to measure TSH in patients with unexplained respiratory failure.