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Plasma spray techniques have been used to increase the Al content on existing NiCoCrAlY films in order to obtain high temperature resistant coatings on Ni-base superalloys for gas turbine applications. Surface alloying has been produced by thermal diffusion under vacuum of the Al and MCrAlY films. This treatment reduces the surface roughness and increases the coating density by sealing its porosity. The aluminides formed have been analyzed in terms of their structural composition and oxidation resistance. Al additions are effective in reducing the oxidation rates, in particular for the MCrAlY coatings which are APS deposited. By increasing the temperature over 1100 °C, the coating efficiency rapidly decreases.

One of the complications of arteriovenous fistulas in chronic hemodialyzed patients is the onset of an aneurysm which can be at risk of rupture.Traditional surgical repair is not always feasible and may not be successful in these cases, leading therefore to the loss of a functioning vascular access and requiring in any case the temporary use of a central venous catheter to allow regular hemodialysis sessions.We applied to this kind of aneurysm the same experience developed in the management of major arterial aneurysms and we considered endografting repair a good alternative in this case. In this paper we present the successful treatment of an arteriovenous fistula aneurysm using that technique.A distal radio-cephalic arteriovenous fistula in one of our patients presented an aneurysm with high risk of rupture. The endografting repair with percutaneous insertion of a Wallgraft™endoprosthesis was well tolerated and the vascular access could be used the day after, without the need for a central venous catheter insertion.

Seroma is one of the most frequent complications of PTFE vascular grafts and its etiology is still unclear. Case report: A 51 year-old male on regular dialytic treatment for seven years underwent the surgical implantation of a vascular prosthesis of homologous safena due to the thrombosis of his native artero-venous fistula. Several years earlier the patient had suffered the amputation of the left forearm because of electric shock. A few months later the vascular prosthesis was replaced with a PTFE vascular graft as a result of aneurysm formation and thrombosis. During the following days a non pulsating swelling occurred near the arterial anastomosis. Ultrasonography, doppler sonography and aspiration confirmed the diagnosis of seroma and it was surgically removed. Some weeks later a new seroma was observed in the same site and associated with a skin ulcer. A new surgical removal had no benefit and about one month later a perigraft collection was found along with signs of bacterial infection.For this reason the patient underwent the surgical excision of the PTFE graft and a vascular access was warranted by placing a Tesio™catheter.Usually surgery is considered mandatory in seromas larger than 2 cm in diameter and showing continuous growth. In our patient the poor vascular status might have suggested a more conservative management even with a seroma diameter of about 7 cm. Nevertheless the high risk of systemic infection prompted us to remove the PTFE graft.

Partial trisomy 9p and a 13/14 translocation occurred in the daughter of a t(5;9)(p15;p12) mother and a t(13;14) (p11;q11) father. Two additional offspring displayed a normal karyotype and a translocation trisomy 13 respectively. Two first cousins, selected for chromosome analysis because of a spontaneous abortion, were found to have an identical translocation t(14;21)(p11;q11). Their second pregnancy was monitored by midtrimester amniocentesis and disclosed a balanced fetus. The different zygotic chromosome constitutions and the counselling problems in the marriages between two balanced translocation carriers are discussed.

Peripheral blood lymphocytes from eight Fanconi anemia (FA) patients, 14 FA heterozygotes, and nine normal subjects have been tested for their susceptibility to chromosomal breakage induction by diepoxybutane (DEB) and by two peroxides. In addition, the effect of five antioxidants was investigated in standard cultures and in cultures stressed either with DEB or with butylhydroperoxide (BHP) or with hydrogen peroxide (H2O2). DEB, BHP, and H2O2 dramatically increased the chromosomal breakage levels in homozygous and heterozygous FA cells. A partial correction of chromosomal instability was obtained by treating the patients' lymphocytes with antioxidants. A “protective” effect was also noted in the DEB or peroxide-stressed lymphocytes of patients and heterozygotes, grown in the presence of antioxidants.

Report is given of a mentally retarded and dysmorphic patient with a partial monosomy 8q, resulting from a de novo translocation t(4;8)(q13; q213).

The purposes of this report are to describe a design for the study of X linkage, to illustrate its application using cognitive test scores, and to offer a linkage hypothesis suggested by these data. Sixty-seven three-son families were examined for two X chromosome marker variables—red-green color vision andXg(a) blood groups—and given a battery of cognitive tests of field dependence and spatial visualization abilities. Evidence was found to suggest that brothers who are identical inXg(a) phenotype are more similar to each other in extent of field dependence than brothers who are different inXg(a) phenotype. This result is tentative because of the small number of informative cases and the many linkage associations examined. If crossvalidated, such a finding would be consistent with the proposition that an X chromosome gene contributes to the field dependence-independence cognitive style.

Abstract: In order to explore the possibility that the assignment of University chairs could be automated, we have carried out a comparative analysis of the relative scientific and technological level of candidates competing nationally for given chairs of first (full professor) and second (associate professor) level, using indicators such as the number of publications and citations in international journals, the number of patents and inventions and few others. This study, contrary to some gloomy opinions, has suggested that at least for what concerns hard science, performances can be measured impartially at least to some extent. Bibliometric indicators, when properly weighted., appear to be effective parameters to monitor degree of excellence in scholastic rating and to establish reliable objective standards. Their utilization, however, to automate the assignment of university chairs appears still questionable and should be limited to the needed provision of computer-assisted selection criteria and reference databank.

Peripheral lymphocytes of three Fanconi's anemia (FA) patients and of five heterozygotes have been tested for their susceptibility to chromosomal breakage and sister chromatid exchange (SCE) induction by diepoxybutane (DEB). As previously shown, DEB dramatically increases the chromosomal breakage level in both homozygotes and heterozygotes. Slightly, but significantly, reduced spontaneous levels of SCE were found in cultures from FA patients and FA gene carriers as compared with controls. SCE rates were not enhanced in lymphocytes grown in the presence of DEB, irrespective of the time at which it had been added to the culture, and were comparable in cells of FA patients and FA heterozygotes. This was in contrast with SCE rates in control cells, which showed increases positively related to the length of DEB treatment.

A male patient with mental retardation and typical clinical features of 10p trisomy syndrome was found to have a duplication of the short arm of chromosome 10 attached to the short arm of the Y chromosome.

Duchenne muscular dystrophy (DMD) is a lethal sex-linked degenerative disorder of the muscle in man. Generalized cell membrane abnormalities seem to be involved in the pathogenesis of the disease; in particular, the impairment of lymphocyte capping capacities has been repeatedly confimed. To clarify whether capping impairment is a consequence of factors related to the activity of the disease or an expression of an intrinsic cellular defect, we have investigated the capping capacities of DMD EBV-transformed cell lines. The results indicate a significant impairment of capping capacity in cultured cell lines, providing evidence for an intrinsic cell deficiency in DMD.

THERE is disagreement about the site of the human haemoglobin structural genes, mapping of which has been attempted by in situ hybridisation1–4and family studies5,6. After in situ hybridisation of human metaphase chromosomes with radioactive globin mRNA Price et al.1suggested that the haemoglobin structural genes are located on the long arm of chromosome 2 and on the long arm of a B-group chromosome, the latter carrying the genes for β, γ and δ chains. Their approach was criticised because of the low specific activity of the 3H-mRNA assay used7,8, but Atwood et al.2and Price and Hirschhorn3,4confirmed the original assignments using human complementary DNA (cDNA). Finally it was decided that the B-group chromosome that carries haemoglobin loci is chromosome 43,4. Family studies gave results consistent with loose linkage between the locus of the MN blood group and β-thalassaemia. The MN blood group has been mapped tentatively on the long arm of chromosome 2 or on the distal end of the long arm of chromosome 4 (refs 9, 10). But the localisation of the MN system on 2q is inconsistent with data from family studies11–13, and the distal segment of 4q has been considered more probable11. For similar reasons the β-globin locus has been mapped tentatively on chromosome 4 (ref. 5). We report here a study of globin synthesis which confirms that chromosome 4 is the site of the structural gene for α-globin.

RECENT work in which clones derived from single haemopoietic cells repopulate the erythroid, myeloid and lymphoid tissues of lethally irradiated mice suggests a common or single stem cell concept for the cells of the haemopoietic system1–3. In man, however, studies of the distribution of the Philadelphia (Ph) chromosome marker of chronic myelogenous leukaemia suggest a common stem cell for erythrocytes and granulocytes and a different stem cell for lymphocytes; this follows from the fact that the Ph chromosome is found in erythrocytic and granulocytic precursors but not in circulating lymphocytes4. We have examined the inter-relationships of the blood cells in normal human subjects, utilizing the mosaicism resulting from Xchromosome inactivation ; specifically, we are asking whether erythrocytes (E), granulocytes (G) and lymphocytes (L) arise from common or from different stem cells.