Twenty-five patients with overt clinical and biochemical findings of porphyria cutanea tarda took part in a study comparing intensive phlebotomy with slow subcutaneous desferrioxamine treatment. Fifteen male patients (Group A) had intensive venesection therapy. Ten patients (Group B) with associated diseases (minor thalassemia, cardiovascular impairment, pulmonary tuberculosis or severe liver cirrhosis) received 1.5 g of desferrioxamine by slow subcutaneous infusion using an automatic syringe pump 5 days a week. No patient complained of appreciable side effects. Serum iron, ferritin and uroporphyrins were normalized in all subjects by the end of treatment. The mean time necessary for complete recovery was 13.8 months (range 9-19) and 11.2 months (range 6-14) in Groups A and B, respectively. Liver function significantly improved during and after the treatments in both groups. We conclude that recovery from porphyria cutanea tarda can be achieved equally well using phlebotomy or desferrioxamine subcutaneous infusion. Phlebotomy is easily performed and remains the treatment of choice; slow subcutaneous desferrioxamine treatment, although expensive, is recommended when severe associated diseases contra-indicate venesection.
The need for accurate and noninvasive evaluation of liver iron stores prompted us to evaluate the reliability of high-field magnetic resonance imaging equipment in liver patients with low or moderate siderosis, given the poor results obtained using systems operating at low field strength in such cases. Twenty patients with sporadic porphyria cutanea tarda and 28 with comparable chronic liver diseases (chronic hepatitis or cirrhosis) and moderate siderosis were compared with 10 patients with idiopathic or secondary hemochromatosis and 10 healthy controls. Plasma iron profile, ferritin concentration and liver iron concentration, determined with atomic absorption spectroscopy, were matched with the magnetic resonance parameters-namely, transverse relaxation time and the signal intensity for a given proton amount, obtained with equipment operating at a field strength of 1.5 T. Hemochromatosis patients with mean liver iron concentrations of 550 mumol/gm dry wt (vs. 10 mumol of controls) exhibited an impressive reduction in the signal intensity with respect to the other three groups, and this reduction prevented any further comparison with the same porphyria cutanea tarda and chronic liver disease groups, whose liver iron level was twice that of the controls. The signal intensity remained almost unchanged in the latter groups, whereas the transverse relaxation time was significantly reduced. Moreover, correlation with liver iron was significantly inverse in the case of the transverse relaxation time (n = 17, r = 0.62, p = 0.008) and direct in the case of the transverse relaxation rate. The transverse relaxation time values returned to normal in five patients who had completed an iron-depletion program.(ABSTRACT TRUNCATED AT 250 WORDS)
The aim of this paper is to evaluate invasive and non-invasive indices of iron store and compare the effectiveness of different ferrodepletive protocols in 150 patients with porphyria cutanea tarda (PCT). Iron removal was performed either by intensive phlebotomy (22 cases) or slow subcutaneous and high intravenous doses of desferrioxamine (18 and 5 cases, respectively), and several laboratory parameters were studied; among these, oligo-elements and urinary porphyrins (detected by HPLC) were taken into account before and after the treatments. Serum iron, transferrin saturation, ferritin (RIA) and nuclear magnetic resonance results were compared with invasive findings in order to detect the metal deposition in liver tissue (atomic absorption concentration, optic or electron-microscopic detection). Liver iron overload was observed in 95% of cases. Full normalization of the disease took place by all the treatments, even if it required slightly more time in the phlebotomy group. We may conclude that ferrodepletive treatments are highly effective in PCT and, considering the fact that siderosis and liver damage always accompany the disease, these treatments are proposed as first choice in such cases.
A number of X-ray astronomical missions of near future (XEUS, Constellation-X, SIMBOL-X, HEXIT-SAT, NEXT) will make use of hard X-ray (10-100 keV) optics with broad-band multilayer coatings. To this aim we are developing a multilayer deposition technique for large substrates based on the e-beam deposition technique, improved by the implementation of an ion beam assistance device, in order to reduce the interfacial roughness and improve the reflectivity. The e-beam deposition with ion assistance keeps the film smoothness at a good level and takes the advantage of a reduction of the interlayer stresses 11 . This approach is well suited for the manufacturing of highreflectance multilayer mirrors for hard X-rays space telescopes where, in addition to a high quality of the deposited films, a volume production is also requested. Moreover, we are also up-grading the replication technique by nickel electroforming, already successfully used for the gold coated soft X-ray mirrors of Beppo-SAX 1 , XMM 2 , JET-X/SWIFT 3 missions, to the case of multilayer coated mirrors. In this paper we will present the technique under development and the implemented deposition facility. Some preliminary, very encouraging, results achieved with the Xray (8.05 and 17.4 keV) and topographic characterization on flat samples will be discussed. SCOPE OF THE WORKThe extension to the hard X-ray band (10 -100 keV) foreseen in next focusing X-ray telescopes will mostly implement multilayer-coated mirrors. A suitable technique for the production of multilayer mirrors is an extension of the Nickel electroforming replication from shaped mandrels 4,5 . This approach is very attractive since, in addition to get very good optical performances, in the case of multimodular telescopes it implies a reduction of cost and integration time since the shells are monolithic and many elements can be replicated from the same master.In order to extend the Ni replication technique to the case to the case of multilayer coated mirrors, in the framework of a development project funded by ASI (the Italian Space Agency) which involves INAF/OAB, Media Lario S.r.l., LABEN, IASF, Politecnico di Milano, we are developing a multilayer deposition technique on mandrels based on the e-beam deposition. The choice of this kind of deposition is determined by the requirement of uniform coating of large surfaces, a feature which is achievable with difficulty with techniques like the ion-beam sputtering. We can, moreover, reuse the same coating facilities installed at Media Lario, which were used to produce the mirrors of XMM by Nickel electroforming replication.
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