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Biomedical subjects

R Mignani

Publications and source records attributed to R Mignani.

13 recordsLinked to original sources
PubMed2003

Geminga's tails: a pulsar bow shock probing the interstellar medium.

We report the X-ray Multimirror Mission-Newton European Photon Imaging Camera observation of two elongated parallel x-ray tails trailing the pulsar Geminga. They are aligned with the object's supersonic motion, extend for approximately 2', and have a nonthermal spectrum produced by electron-synchrotron emission in the bow shock between the pulsar wind and the surrounding medium. Electron lifetime against synchrotron cooling matches the source transit time over the x-ray features' length. Such an x-ray detection of a pulsar bow shock (with no Halpha emission) allows us to gauge the pulsar electron injection energy and the shock magnetic field while constraining the angle of Geminga's motion and the local matter density.

Journal Article↗
PubMed1996

Ethylene-oxide and steam-sterilised polysulfone membrane in dialysis patients with eosinophilia.

Eosinophilia and some acute dialysis side-effects, such as itching, flushing and bronchospasm, are often associated with the presence of ethylene oxide (ETO) as dialyzer sterilizing agent. This study evaluated the effects of two different polysulfone (PS) hollow-fiber dialysers sterilized with ETO and steam in 31 chronic dialysis patients with eosinophilia. Clinical symptoms, metabolic and biochemical parameters, complement (C3a and C5a) activation and production were evaluated in each patient dialysed for two months at a time with Cuprophan dialyser, ETO-PS dialyser and steam-PS dialyser. The steam-sterilizer agent does not alter the purifying capacity of the PS membrane which maintains its superiority over Cuprophan in terms of biocompatibility. Using steam-PS, intradialytic eosinophil kinetics seems to improve. In some patients with high serum levels of ETO-specific IgE these levels tend to diminish. Generic intradialytic symptoms do not differ between the two sterilization methods, although some hypersensitivity symptoms during the first dialysis hour are considerably lower in some patients when steam-sterilized PS is used.

Adult↗
PubMed1990

[Destructive cervical amyloidotic spondyloarthropathy in patients undergoing periodic dialysis. Personal experience].

The accumulation of amyloid (beta 2-microglobulin) in several organs and tissues of patients in chronic dialysis is a recent pathologic condition. A wide range of cases, supported by specific tests for amyloid on bioptic and autoptic samples, showed a radiographic semiology of osteostructural alterations in various areas which allows amyloidotic condition of bone to be diagnosed with high reliability. In 11 of 62 patients (17.74%) we observed destructive cervical amyloidotic spondyloarthropathy (DCAS). The radiological patterns common to all patients were subchondral sclerosis, erosions of vertebral body plates, widening/narrowing of intervertebral spaces, no/poor osteophytosis. Over-hanging was present in 54.5% of cases, and deformation of vertebral bodies in 45.4%. CT was useful in improving the definition of the various alterations, and in locating others, such as cavitations in vertebral bodies and involvement of apophyseal joints. Constant factors were the association with extravertebral osseous amyloidosis, dyalitic age over 60 months, and the use of Cuprophan membranes for dialysis. The frequent (72.72%) association with alterations involving the lumbar rachis (subchondral sclerosis, erosions and geodes) was suggestive of amyloidotic condition.

Amyloidosis↗