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Alessandro Martini

Publications and source records attributed to Alessandro Martini.

24 records · Page 2Linked to original sources
PubMed2002

Human leukocyte antigen-A, -B, -C and -DR alleles and soluble human leukocyte antigen class I serum level in Ménière's disease.

Previous studies have suggested that many human leukocyte antigen (HLA)-A, -B, -C and -DR alleles are associated with Ménière's disease (MD), an inner ear disorder with a proposed autoimmune etiopathogenesis. Despite some discrepancies many reports are in agreement with a hypothesis suggesting an influence of serologically detected HLA-C products in the susceptibility to the disease. To confirm these data we investigated the distribution of HLA-A, -B, -C and -DR antigens that well define the HLA polymorphism using DNA typing. Furthermore, as autoimmune factors have been claimed to play a role in MD, we investigated the serum level of soluble HLA class I (sHLA-I). Molecular typing of HLA class I and II was performed using polymerase chain reaction sequence-specific primers in 41 patients affected by MD, 34 patients affected by other inner ear diseases (OIDs) and 101 healthy subjects. An ELISA technique was employed to investigate the serum level of sHLA-I in 17 MD patients, 10 OID patients and 83 healthy subjects. The results showed a significantly increased frequency of the Cw*07 specificities in MD patients when compared to OID patients (63.4% vs 32.3%; p = 6.9 x 10(-3); relative risk [RR] = 3.6) and healthy subjects (63.4% vs 35.6%; p = 2.28 x 10(-3); RR = 3.1). The sHLA-I concentrations detected in sera did not differ significantly between MD patients (616 +/- 271 ng/ml), OID patients (570 +/- 307 ng/ml) and healthy subjects (518 +/- 340 ng/ml).

Case-Control Studies↗
PubMed2002

Multicenter comparison of three different analytical systems for evaluation of DNA banding patterns from Cryptococcus neoformans.

The enormous improvement of molecular typing techniques for epidemiological and clinical studies has not always been matched by an equivalent effort in applying optimal criteria for the analysis of both phenotypic and molecular data. In spite of the availability of a large collection of statistical and phylogenetic methods, the vast majority of commercial packages are limited by using only the unweighted pair group method with arithmetic mean algorithm to construct trees and by considering electrophoretic pattern only as migration distances. The latter method has serious drawbacks when different runs (separate gels) of the same molecular analysis are to be compared. This work presents a multicenter comparison of three different systems of banding pattern analysis on random amplified polymorphic DNA, (GACA)(4), and contour-clamped homogeneous electric field patterns from strains of Cryptococcus neoformans var. neoformans isolated in different clinical and geographical situations and a standard Saccharomyces cerevisiae strain employed as an outgroup. The systems considered were evaluated for their actual ability to(i) recognize identities, (ii) define complete differences (i.e., the ability to place S. cerevisiae out of the C. neoformans cluster), and (iii) estimate the extent of similarity among different strains. The ability to cluster strains according to the patient from which they were isolated was also evaluated. The results indicate that different algorithms do indeed produce divergent trees, both in overall topology and in clustering of individual strains, thus suggesting that care must be taken by individual investigators to use the most appropriate procedure and by the scientific community in defining a consensus system.

Algorithms↗
PubMed2002

Comparison of transient otoacoustic emission responses from neonatal and adult ears.

Transient otoacoustic emission (TEOAE) responses from neonatal (age: 48 h) and adult subjects (age: 26.6 +/- 10.0 yr) were analyzed by the combined use of recurrence quantification analysis and singular value decomposition. The data from the two age groups showed significant differences and similarities. The neonatal responses presented less deterministic structures than those of the adults in terms of recurrent dynamic features. In both data sets, the same high level of individual specific dynamic features was observed. The results from the singular value decomposition analysis suggest that a large percentage of variability in all of the analyzed responses can be explained by four to five essential modes. This number is lower than that observed in simulated TEOAE responses generated by a five-component gammatone model. A possible explanation is presented, based on simple instrumental and morphoanatomic considerations.

Adult↗
PubMedDate not supplied

Gentamicin-induced cytotoxicity involves protein kinase C activation, glutathione extrusion and malondialdehyde production in an immortalized cell line from the organ of corti.

The objective of the present study was to investigate the biochemical mechanisms underlying gentamicin cytotoxicity in OC-k3 cells derived from an immortalized cell line developed from the organ of Corti of transgenic mice. Administration of 50 microM gentamicin significantly reduced cell proliferation and viability, as well as initiating morphological changes associated with apoptosis. Protein kinase C (PKC) alpha activity was increased in gentamicin-treated cells, peaking 15 min after dosing (+138.2%). This PKCalpha increase was followed by a rise of glutathione (GSH) efflux and a concomitant 29% decrease in intracellular GSH levels at 30 min. PKCalpha-specific inhibitors blocked these cytotoxic effects. Gentamicin also increased malondialdehyde levels, while N-acetylcysteine, GSH and ascorbic acid prevented gentamicin-induced cell death. These findings suggest that gentamicin cytotoxicity involves a production of intracellular reactive oxygen species and a concomitant PKC-dependent fall of intracellular scavenging abilities (GSH), events that together drive cells to undergo apoptosis.

Animals↗
PubMedDate not supplied

Correlation among phenotypical and molecular techniques in comparing ascomycetous yeast type strains.

Different phenotypical or molecular techniques can be used to describe and classify microorganisms for taxonomic, phylogenetic or genetic purposes. In yeast taxonomy the official hierarchic classification, based on morphological and physiological characters, is used together with more convenient molecular techniques such as the DNA sequencing. The question on whether these procedures produce coherent classifications is critical both to interpret taxonomic data consistently and to outline species correctly. In this paper, a set of type strains from the major genera of the budding hemiascomycetes yeast is examined with a series of physiological and molecular techniques, widely employed in taxonomy, in order to compare the among-strains correlations obtained with different methods. Results showed that the level of correlation among different techniques is relatively low, showing that different classifications and species organization could be obtained with diverse approaches. This is particularly interesting, considering that the official description of the yeast species is based on characters different from those becoming increasingly popular in the routine identification.

Animals↗