Biomedical subjects

A Sinatra

Publications and source records attributed to A Sinatra.

At least 19 recordsLinked to original sources

PubMed2005

Long-lived quantum memory with nuclear atomic spins.

We propose to store nonclassical states of light into the macroscopic collective nuclear spin (10(18) atoms) of a 3He vapor, using metastability exchange collisions. These collisions, commonly used to transfer orientation from the metastable state 2 3S1 to the ground state of 3He, can also transfer quantum correlations. This gives a possible experimental scheme to map a squeezed vacuum field state onto a nuclear spin state with very long storage times (hours).

Journal Article↗

PubMed2001

Classical-field method for time dependent Bose-Einstein condensed gases.

We propose a method to study the time evolution of Bose-Einstein condensed gases perturbed from an initial thermal equilibrium, based on the Wigner representation of the N-body density operator. We show how to generate a collection of random classical fields sampling the initial Wigner distribution in the number conserving Bogoliubov approximation. The fields are then evolved with the time dependent Gross-Pitaevskii equation. We illustrate the method with the damping of a collective excitation of a one-dimensional Bose gas.

Journal Article↗

PubMed1989

A comparative assay of epidemiological markers for Acinetobacter strains isolated in a hospital.

A comparative assay for epidemiological evaluation of three different Acinetobacter typing procedures, i.e. biotyping, phage-typing, and the analysis of the bacterial envelope protein profiles, was carried out using sixty-four multiresistant Acinetobacter strains isolated from clinical specimens. The antibiotic susceptibility of the strains was also considered. After geno-species identification, biotyping allowed the recognition of a relatively large and long-lasting presence, at an Intensive Therapy Unit, of two A. baumannii biotypes. Phage-typing and the analysis of the susceptibility to antibiotics allowed for the differentiation of strains belonging to different geno-species and biotypes, and in some cases also to the same biotypes. On the contrary, the analysis by polyacrylamide gel electrophoresis of the cell-envelope proteins failed to show any diversity not only within, but also between some of the biotypes of A. baumannii, the most prevalent species of the genus in the hospital environment.

Acinetobacter↗

PubMed1985

Infections caused by Pseudomonas aeruginosa: relatively frequent isolation of serogroup 12 from clinical specimens.

Serological typing of P. aeruginosa is the most simple and reliable procedure recommended for "in-house" investigations and for studies of suspected outbreaks of infection by this microorganism. It is also a useful procedure in order to know serotype prevalence in a definite geographical area and to obtain indications about the more appropriate composition of polyvalent anti-Pseudomonas vaccines. In the present report, we describe the relatively high frequency of isolation of serogroup 12 from patients in Palermo, Italy. Serogroup 12 is very rare in north-Europe and in the USA, and, as a consequence, it is not included in some vaccine preparations. In Palermo, strains belonging to this serogroup, resistant to a large number of antibiotics, were on the contrary isolated, during more than six years, in different hospitals and from three out-patients. In a Burns Unit, they were in particular responsible for extensive and life-threatening outbreaks.

Bacterial Vaccines↗

PubMed1984

Measles virus variants: viral replication and cytopathogenicity in human T lymphocytes and B lymphoblastoid cells.

Measles virus can replicate in circulating T cells, B cell and monocytes of man as well as in different human lymphoblastoid cell lines. In the present report we describe the effects on lymphoblastoid cells and on a defined population of human T lymphocytes of infection with three measles virus variants characterized by different cytopathogenicity in human and simian epithelial cell lines. The aim of the investigation was to establish some evidence that the evolution of the viral infection and the cellular damage in lymphocytes can be directly controlled by viral properties.

Cell Line↗

PubMed1983

Rotavirus persistence in cell cultures: selection of resistant cells in the presence of foetal calf serum.

The Lincoln strain of bovine rotavirus, cytocidal for bovine AU-BEK cells, can establish in the same cell cultures in the presence of foetal calf serum (FCS) a persistent infection that depends on selection of highly resistant cells. In fact, after the induction of the carrier state only a small fraction of the cell population was infected. The parental and the carried viruses are not demonstrably different, the cultures are resistant to superinfection by the homologous virus, the cultures can be cured by antiviral serum in the medium and uninfected resistant cell clones can be selected. The presence of FCS was essential during induction and maintenance of persistence. Its effects appear to be exerted not on the control of virus replication in fully sensitive cells but on the proliferation and selection of the resistant cells.

Animals↗

PubMed1983

[Immunofluorescence reaction for rotavirus analysis in fecal specimens].

Testing for rotavirus detection in faeces from infants with acute diarrhea can be carried out, with high sensitivity, by immunofluorescence on rhesus monkey kidney cell lines (MA-104). Preincubation of viral inoculum with trypsin enhances further the sensitivity. In the present study we tried to assess the optimal conditions for detection of viral antigens, by analyzing the expression of virus-specific proteins at different times of infection and the effects of trypsin presence during virus adsorption and replication. Maximal production of viral antigens was obtained by infecting the cells 4 hours after cell-seeding and incubating them for 18 hours afterwards. In experiments with simian rotavirus SA-11, pretreated with trypsin and then with a trypsin inhibitor, a marked reduction in the percentage of fluorescent cells was observed thus indicating a role of the enzyme both on the virus and on the cell layer.

Antigens, Viral↗

PubMed1980

[Septic complications, due to the catheter, in parenteral nutrition and continuous peridural anesthetic block. Cases from an intensive care center].

The results of the bacteriologic studies carried out on 192 catheters used for parenteral nutrition and continuous peridural block on 98 patients are reported together with the incidence of infections. The reported data emphasize the importance of the sterile precautions while no correlation seems to exist between the bacterial contamination and the length of stay of the catheter.

Catheterization↗

PubMed1980

[The use of sodium cefoxitin in resuscitation and intensive therapy].

The cefoxitin sodium has been used in 20 patients with surgical infections admitted in out Intensive Care Unit. This antibiotic was administered by central venous catheter and in 9 patients was associated with other antibiotics. 75% of the patients so treated was cured and no side effects were noted. The seriousness of the infective process was most likely responsible of the 25% of failure.

Adolescent↗

PubMed1978

Latent measles virus infection in Vero cells depending on a temperature-sensitive phenomenon.

A latent infection by measles virus in a line of Vero cells could be maintained only at 37 degrees C. The conditions of temperature nonpermissiveness were associated with some block in virus production and/or release and with the establishment of an autointerference phenomenon. Reduction of the incubation temperature to 33.5 degrees C induced a rather rapid transition from the latent to a lytical infection with a recue of virus. The rescued virus exhibited a restricted capacity to grow at 37 degrees C.

Animals↗

PubMed1976

Studies on a measles virus variant inducing persistent infections in cultured cells.I. Isolation and characterization of plaque purified virus clones.

Attempts were made to characterized by a plaque assay two variants of the Edmonston strain of measles virus and to obtain plaque purified virus populations. The UP non-cytocidal variant, in all the examined cell systems, mainly produced small but also large plaques; the DP cytocidal variant always large plaques. Three clones, UP-SP4, UP-LP4 and DP-LP4, were derived by plaque purfication respectively of the UP small plaque, UP large plaque and DP large plaque forming particles. The virus populations of the clones could be distinguished by some other biological and physical characters: cytopathic effect in roller tube cultures, growth potential in HeLa cells, thermal stability at 45 degrees C, stability of the properties during serial passages at different input multiplicity. The hypothesis was supported that the typical properties of the UP and DP variants are host-independent and genetically controlled viral markers.

Animals↗

PubMed1976