The Skeleton of the Manus of Scelidotherium (Xenarthra,Mylodontidae) Specimens from the Pleistocene of the Province of Córdoba,Argentina, and its Systematic Implications

Journal of Mammalian Evolution - Dental and craniomandibular data have been predominantly used to infer relationships among mylodontid ground sloths. Recent studies indicate the osteology of the...     

Medicine, public health, and the ethics of rationing.

Physicians, like all citizens, have communal and private identities, each attending various associated roles and fulfilling diverse obligations. In light of these dual personae, we seek a moral philosophy which encompasses the responsibility for providing care to the patient and at the same time acknowledges the physician's role of arbiter of distributed care. In the traditional doctor/patient relationship, rationing, the admission that health resources are limited and must be distributed equitably by universally accepted criteria, is essentially ignored. When the physician assumes a population-based system of ethics to optimize care for all patients within a group, rationing is embraced as the realistic admission that any social action resides within boundaries--in this case health care resources--and that such restraints have economic consequences that present ethical choices. A common ground to accommodate these dual allegiances is offered by communitarian philosophy, whose outline and applicability is presented here as an alternative to the apparent moral opposition of optimized individual care and the requirement of community-wide distribution of limited health resources.     

Évaluation quantitative préliminaire du 18F-FDDNP en TEP/TDM dans la maladie d’Alzheimer,en utilisant différentes régions de référence

IntroductionAlzheimer's disease (AD) is the leading cause of dementia in the world. His current treatment is symptomatic. New therapies, aimed at slowing the neurodegenerative process, are actually under study. Early detection of AD as also the evaluation of new generation of neuroprotectors drugs is essential. For this reason, markers of amyloid plaques and neurofibrillary lesions have been developed including ¹⁸F-FDDNP.MethodsTwo patients and two controls were included in this preliminary study. They were submitted to a PET/CT with ¹⁸F-FDDNP. Data acquisition was performed in a list mode during 90 minutes. We used a cerebral atlas to create ROI, after co registration with a perfusion PET template, and we estimated the distribution volume ratio (DVR) using two different reference regions: the cerebellum and the white matter. We calculated a simplified index of quantification (SUVr) using a single 10 minutes acquisition frame.ResultsWe found an increased DVR in temporal lobes (amygdala) (1.23–1.40 in patients vs 1.06–1.31 in controls, with cerebellum as reference region) and fronto-basal regions (1.48–1.30 in patients vs 1.16–1.23 in controls with the same reference region and 1.25–1.18 in patients vs 1.13–1.19 in controls with white matter as reference region). SUVr calculated between 50 and 60 minutes after injection was highly correlated to DVR values (correlation coefficient 0.93). The SUVr difference between patients and controls was more important with cerebellum rather than white matter as reference region (26% in amygdala).ConclusionThis is a very preliminary study due to the low number of subjects included. However, the results obtained suggest the feasibility of brain ROI segmentation and the DVR-SUVr calculation using an anatomical atlas.     

The human neutrophil oxygen armory

The human neutrophil respiratory burst, initiated by the activation of the flavoenzyme NADPH-oxidase, generates the one-electron reduction product of oxygen, O₂⁻. Derivative free radicals and products of the myeloperoxidase-H₂O₂-halide system are toxic to micro-organisms and cytolytic to normal and malignant mammalian cells. Current interest has focused on the intra- and extra-cellular molecular targets of the respiratory burst products to define the complex pathways by which these metabolites participate in the inflammatory reaction.