Biomedical subjects

R Murgia

Publications and source records attributed to R Murgia.

7 recordsLinked to original sources

PubMed1997

Oligonucleotides specific for pathogenic and saprophytic leptospira occurring in water.

Sets of primers specific for both pathogenic (SPL) and saprophytic (SSL) Leptospira were designed from ribosomal 16S genes (rrs) available in databases. They were used as two sets of primer pairs for the PCR amplification of known pathogenic and saprophytic strains. It was possible to identify pathogenic strains by the use of SPL primers and saprophytic ones by SSL primers. Serovars from L. meyeri, of controversial pathogenicity status, confirmed the heterogeneity of the species representatives in this respect. Serovars ranarum, sofia and perameles were amplified by SPL and not SSL. Conversely, serovar semaranga was amplified by SSL and not SPL. In order to use SPL primers for the detection of pathogenic leptospires from a natural water environment, we set up an additional semi-nested PCR by employing a second internal primer which succeeded in detecting as few as 5 pathogenic leptospires per ml of water.

DNA, Bacterial↗

PubMed1996

Leptospira interrogans and Leptospira peptidoglycans induce the release of tumor necrosis factor alpha from human monocytes.

Elevated plasma concentrations of the cytokine tumor necrosis factor alpha (TNF alpha) have been observed in patients affected by leptospirosis. In this study we found that a preparation of peptidoglycan of Leptospira interrogans, serovar copenhageni, was able to induce the release of TNF alpha from peripheral blood mononuclear cells. TNF alpha induction occurred in a dose dependent manner and was not affected by the endotoxin inhibitor polymixin B. This is the first report on induction of TNF alpha release by a peptidoglycan of spirochetes. Our findings are consistent with existing clinical data and provide a potential mechanism for TNF alpha production.

Biological Assay↗

PubMed1996

IgM and IgG significant reactivity to Borrelia burgdorferi sensu stricto, Borrelia garinii and Borrelia afzelii among Italian patients affected by Lyme arthritis or neuroborreliosis.

This survey evaluates the specificity of band patterns in immunoblot of sera taken from clinically defined cases of Lyme arthritis and neuroborreliosis, towards three locally isolated strains of Borrelia burgdorferi, belonging to the three species: Borrelia sensu stricto, Borrelia garinii and Borrelia afzelii. To assess specificity, patient sera were statistically (X2, P < or = 0.05) compared with blood donors sera samples. Both IgG and IgM antibodies were considered. The overall reactivity of the three Borrelia strains in IgG immunoblots indicated that ten protein bands were significant, with a different prevalence of some of them in the two groups of patient sera: bands at 60-58, 30-33, 36-37 and 28-27 kDa were markers for neuroborreliosis sera; proteins at 100-83, 72-70 and 18-17 kDa behaved like markers for Lyme arthritis. The IgM Immunoblots revealed significant bands at 100-83, 72-70, 51, 24-21 and 18-17 kDa only with neuroborreliosis sera. Though there were variable band reactivities in each strain, a correlation emerged between the three genospecies and the clinical symptoms: in fact B. afzelii and B. garinii were prevalent in Lyme arthritis sera, (IgG Immunoblots); B. garinii was associated to neuroborreliosis (IgG and IgM Immunoblots); B. sensu stricto was strongly reactive with neuroborreliosis in IgM immunoblots. These data indicate that the three locally strains of Borrelia representing the three genospecies should be used together in immunoblot to detect antibodies elicited in neuroborreliosis and Lyme arthritis.

Antibodies, Bacterial↗

PubMed1995

Prevalence of IgG reactivity in Lyme borreliosis patients versus Borrelia garinii and Borrelia afzelii in a restricted area of Northern Italy.

This survey evaluates the antibody band patterns of sera taken from clinically defined cases of Lyme borreliosis, towards three locally isolated strains of Borrelia burgdorferi, belonging to the three species: Borrelia sensu stricto, Borrelia garinii and Borrelia afzelii, by means of Western blot. The sera were taken from patients resident in a limited area of Friuli Venezia Giulia (FVG) region. The data indicated that, besides a different feature of the band reactivity which correlated to the different stages of Lyme borreliosis, there was a preferential reactivity to the species Borrelia afzelii and Borrelia garinii. An immunodominant band at 51 kDa, corresponding to a protein visible in the electrophoretic profile of strain BL3 (B. afzelii), behaved like a marker of an early infection, because it was present exclusively in the sera of patient with ECM. The overall findings would indicate that B. afzelii and B. garinii are the prevalent genospecies in the FVG area, even if strains belonging to B. sensu stricto have been also isolated in this area. Consequently strains representative of these two species must be used as antigens in Western blot.

Antibodies, Bacterial↗

PubMed1994

Simultaneous measurement by flow cytometry of phagocytosis and metabolic burst induced in phagocytic cells in whole blood by Borrelia burgdorferi.

This paper describes the interactions between a strain of Borrelia burgdorferi and phagocytic cells, measured in whole blood, by a two-color flow cytometric method, which allowed the simultaneous quantification of both the phagocytosis rate and the oxidative burst activation. The data obtained indicated that: a) phagocytosis and metabolic activation increased as a function of spirochete concentration; b) the number of ingesting cells peaked within 10 min but activation followed later, and did not involve all the phagocytosing cells; c) opsonization of borreliae with a patient's serum enhanced the two cellular activities, mostly phagocytosis. The intensity of such functions was lower than those found for Staphylococcus aureus. The flow cytometric assay of phagocytes interactions with Borrelia burgdorferi assessed in whole blood represents an experimental approach which simulates the physiological conditions in nature.

Blood↗

PubMed1993

[Acromegalic arthropathy].

Six acromegalic patients, three males (aged 28 to 48 years) and three females (aged 57 to 75 years), with GH-producing pituitary adenoma, were studied through clinical examination, laboratory and instrumental tests. In all the patients frequent involvement of large joints, with crepitus and provoked pain, was found; while articular mobility was normal especially in the dorso-lumbar spine, a frequent seat of pain. Radiology showed typical features of an osteoarthritic process with characteristic widening of articular spaces, especially in weight-bearing large joints in symptomatic patients. The evolution of this arthropathy lead to anatomo-clinical pictures almost indistinguishable from osteoarthritis; however, in the early stages, the marked cartilaginous hypertrophy is responsible for peculiar anatomo-radiological pictures, principally represented by widening of articular spaces and intervertebral discal spaces, especially in the dorso-lumbar spine. As far as bone metabolism is concerned, neoproduction and reabsorption, both increased, proceed simultaneously; bone mass reduction is described in some segments. In our study, the two patients with active acromegaly showed bone mass reduction in the lumbar spine.

Acromegaly↗

PubMedDate not supplied

[Results of an airborne spore study in various regions of southern Sardinia].

Fungal air spores can play a significant role in several allergic manifestations. Therefore, the identification of geographic areas of mould distribution could be helpful to the clinician, especially if associated with fungal air spore recording in homes or working environments of sensitized subjects, in determining the real clinical importance of sensitization to fungi. On this basis, we studied the occurrence of airborne fungi at two urban sites and at two rural sites in the South of Sardinia, from May 1987 to April 1988, using the gravity plate method. Our survey has pointed out a significant difference about the occurrence of airborne spores in the areas sampled. Spore concentrations were lower at the urban sites during all the survey period. On the whole 6319 fungal colonies belonging to 28 different genera have been found. Cladosporium, Alternaria, Penicillium and Aspergillus, represented by a range of species, were the most common fungi identified in all sites examined. Remarkable the incidence of Yeasts, represented by the genera Candida, Saccharomyces, Rhodotorula and Sporobolomyces. Aureobasidium, Stemphilium, Botrytis, Chaetomium, Mucor and Rhizopus have been found in all sites but they have not been steadily isolated during the survey. Several other genera have been found only sporadically. Our results seem to confirm that fungal air spores, because of its quantity and variety, can represent a serious problem for human health in Sardinia.

Air Microbiology↗