Assessment and topographic characterization of locoregional recurrences in head and neck tumours

Purpose: To evaluate the differences between three methods of classification of recurrences in patients with head and neck tumours treated with Radiation Therapy (RT). Materials and methods: 367 patients with head and neck tumours were included in the study. Tumour recurrences were delineated in the CT images taken during patient follow-up and deformable registration was used to transfer this volume into the planning CT. The methods used to classify recurrences were: methodCTV quantified the intersection volume between the recurrence and the Clinical Target Volume (CTV); methodTV quantified the intersection between the Treated Volume and the recurrence (for method CTV and TV, recurrences were classified in-field if more than 95% of their volume were inside the volume of interest, marginal if the intersection was between 20-95% and outfield otherwise); and methodCOM was based on the position of the Centre Of Mass of the recurrence. A dose assessment in the recurrence volume was also made. Results: The 2-year Kaplan-Meier locoregional recurrence incidence was 10%. Tumour recurrences occurred in 22 patients in a mean time of 16.5 ± 9.4 months resulting in 28 recurrence volumes. The percentage of in-field recurrences for methods CTV, TV and COM was 7%, 43% and 50%, respectively. Agreement between the three methods in characterizing individually in-field and marginal recurrences was found only in six cases. Methods CTV and COM agreed in 14. The percentage of outfield recurrences was 29% using all methods. For local recurrences (in-field or marginal to gross disease) the average difference between the prescribed dose and D 98% in the recurrence volume was -5.2 ± 3.5% (range: -10.1%-0.9%). Conclusions: The classification of in-field and marginal recurrences is very dependent on the method used to characterize recurrences. Using methods TV and COM the largest percentage of tumour recurrences occurred in-field in tissues irradiated with high doses. Keywords: Head and neck tumours, Radiation therapy, Characterization of tumour recurrences, Geometric methods, Dosimetric assessmen

A change in the optical polarization associated with a gamma-ray flare in the blazar 3C 279

It is widely accepted that strong and variable radiation detected over all accessible energy bands in a number of active galaxies arises from a relativistic, Doppler-boosted jet pointing close to our line of sight. The size of the emitting zone and the location of this region relative to the central supermassive black hole are, however, poorly known, with estimates ranging from light-hours to a light-year or more. Here we report the coincidence of a gamma-ray flare with a dramatic change of optical polarization angle. This provides evidence for co-spatiality of optical and gamma-ray emission regions and indicates a highly ordered jet magnetic field. The results also require a non-axisymmetric structure of the emission zone, implying a curved trajectory for the emitting material within the jet, with the dissipation region located at a considerable distance from the black hole, at about 10^5 gravitational radii.Comment: Published in Nature issued on 18 February 2010. Corresponding authors: Masaaki Hayashida and Greg Madejsk

SEROLOGICAL SURVEY OF Ehrlichia SPECIES IN DOGS, HORSES AND HUMANS: ZOONOTIC SCENERY IN A RURAL SETTLEMENT FROM SOUTHERN BRAZIL

SUMMARY The aims of this study were to determine the seroprevalence of Ehrlichia spp. and risk factors for exposure in a restricted population of dogs, horses, and humans highly exposed to tick bites in a Brazilian rural settlement using a commercial ELISA rapid test and two indirect immunofluorescent assays (IFA) with E. canis and E. chaffeensis crude antigens. Serum samples from 132 dogs, 16 horses and 100 humans were used. Fifty-six out of 132 (42.4%) dogs were seropositive for E. canis. Dogs > one year were more likely to be seropositive for E. canis than dogs ≤ one year (p = 0.0051). Ten/16 (62.5%) and 8/16 (50%) horses were seropositive by the commercial ELISA and IFA, respectively. Five out of 100 (5%) humans were seropositive for E. canis and E. chaffeensis. Rhipicephalus sanguineus (n = 291, 97.98%) on dogs and Amblyomma cajennense (n = 25, 96.15%) on horses were the most common ticks found. In conclusion, anti-Ehrlichia spp. antibodies were found in horses; however, the lack of a molecular characterization precludes any conclusion regarding the agent involved. Additionally, the higher seroprevalence of E. canis in dogs and the evidence of anti-Ehrlichia spp. antibodies in humans suggest that human cases of ehrlichiosis in Brazil might be caused by E. canis, or other closely related species

Identification and mapping of the nursing diagnoses and actions in an Intensive Care Unit

This is a descriptive study with the aim of examining the nursing diagnoses labels and actions prescribed by nurses in the clinical records of patients hospitalized in an Adult Intensive Care Unit. A sample of 44 clinical records was obtained and a total of 1087 nursing diagnoses and 2260 nursing actions were identified. After exclusion of repetitions 28 different nursing diagnoses labels and 124 different nursing actions were found. Twenty-five nursing diagnoses labels were related to human psychobiological needs and three to psychosocial needs. All the nursing actions were mapped to the physiological needs and also to interventions of the Nursing Interventions Classification-NIC. Concordance of 100% was obtained between the experts in the validation process of the mapping performed, both for the nursing diagnoses labels and actions. Similar studies should be conducted for the identification and development of nursing diagnoses and actions.Se trata de un estudio descriptivo con el objetivo de analizar los registros de los títulos de diagnóstico y las acciones de enfermería prescritas por enfermeros en las fichas de pacientes internados en una Unidad de Terapia Intensiva de Adultos. Se obtuvo una muestra de 44 fichas. Se identificaron 1.087 diagnósticos y 2.260 acciones de enfermería. Después de la exclusión de repeticiones se encontró 28 diferentes títulos de diagnóstico y 124 diferentes acciones de enfermería. Veinte y cinco títulos de diagnóstico están relacionados a las necesidades humanas psicobiológicas y tres a las necesidades psicosociales. Todas las acciones de enfermería fueron mapeadas a las necesidades psicobiológicas y también a las intervenciones de la Clasificación de las Intervenciones de Enfermería-NIC. Se obtuvo 100% de concordancia entre los expertos en el proceso de validación del mapeo realizado, tanto de los títulos de diagnóstico como de las acciones de enfermería. Estudios semejantes deben ser conducidos para la identificación y evolución de diagnósticos y acciones de enfermería.Trata-se de estudo descritivo com o objetivo de analisar os registros dos títulos diagnósticos e as ações de enfermagem prescritas por enfermeiros, nos prontuários de pacientes internados em uma unidade de terapia intensiva de adultos. Obteve-se amostra de 44 prontuários. Identificaram-se 1.087 diagnósticos e 2.260 ações de enfermagem. Após exclusão de repetições, foram encontrados 28 diferentes títulos diagnósticos e 124 diferentes ações de enfermagem. Vinte e cinco títulos diagnósticos estão relacionados às necessidades humanas psicobiológicas e três às necessidades psicossociais. Todas as ações de enfermagem foram mapeadas às necessidades psicobiológicas e, também, às intervenções da classificação das intervenções de enfermagem-NIC. Obteve-se 100% de concordância entre os expertos, no processo de validação do mapeamento realizado, tanto dos títulos diagnósticos quanto das ações de enfermagem. Estudos semelhantes devem ser conduzidos para a identificação e evolução de diagnósticos e ações de enfermagem