Cutaneous polyarteritis nodosa in a child and a review of the literature

The cutaneous form of polyarteritis nodosa in children is extremely rare. Findings are usually limited to the skin, muscles and joints. It has a benign but often chronic course. We describe an 8-y-old girl with cutaneous PAN, with extensive livedo reticularis on lower and upper extremities, tender subcutaneous nodules, arthralgia and right ankle swelling. Skin biopsy revealed vasculitis of small and medium-sized blood vessels characterized by fibrinoid necrosis. The use of prednisolone resulted in clinical improvement initially, but recurrence occurred during tapering. She showed marked improvement with additional high dose methyl prednisolone monthly.     

View-invariant representations of familiar objects by neurons in the inferior temporal visual cortex

A view-invariant representation of objects in the brain would have many computational advantages. Here we describe a population of single neurons in the temporal visual cortex (IT) that have view-invariant representations of familiar objects. Ten real plastic objects were placed in the monkeys' home cages for a period of time before neurophysiological experiments in which neuronal responses were measured to four views of each object. The macaques performed a visual fixation task, and had never been trained in object discrimination. The majority of the visual neurons recorded were responsive to some views of some objects and/or to the control stimuli, as would be expected from previous studies. However, a small subset of these neurons were responsive to all views of one or more of the objects, providing evidence that these neurons were coding for objects, rather than simply for individual views or visual features within the image. This result was confirmed by information theoretic analyses, which showed that the neurons provided information about which object was being seen, independently of the view. The coding scheme was shown to be sparse distributed, with relatively independent information being provided by the different neurons. Hypotheses about how these view-invariant cells are formed are described.      

Acute Bilateral Blindness

Acute bilateral blindness is an emergent condition that may signal life-threatening disease. This article details an emergency medicine approach to the patient with acute bilateral blindness, and reports a case of an elderly woman whose sole presenting complaint was acute loss of vision. She was ultimately diagnosed as having pulmonary embolism. The approach focuses on identification of life-threatening disease processes, while differentiating between ocular. psychogenic, and cortical etiologies.     

Interviews of individuals diagnosed as anti-human immunodeficiency virus-positive through the screening of blood donations in the Paris area to 1994: reflections on the selection of blood donors

BACKGROUND: One of the aims of the medical interview routinely preceding each blood donation is the identification of individuals with a risk factor for infection with the human immunodeficiency virus (HIV). STUDY DESIGN and METHODS: Interviews were performed with individuals diagnosed as being seropositive for HIV through the systematic biologic screening of blood donations in the Paris area to establish, first, the circumstances allowing HIV-seropositive individuals to pass through the predonation medical interview and, second, the motivation of these individuals as blood donors. Risk factors of 30 HIV-infected donors identified between 1991 and 1994 were determined. RESULTS: When asked whether they recognized the eventual risk to recipients of donated blood, 14 (47%) of 30 answered positively. Fifteen (50%) admitted having given their blood to determine their HIV status. CONCLUSION: These individuals did not exclude themselves from blood donation and probably hid their risk factor(s) at the predonation interview in order to be accepted as blood donors.