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A Recchia

Publications and source records attributed to A Recchia.

14 recordsLinked to original sources
PubMed1999

Site-specific integration mediated by a hybrid adenovirus/adeno-associated virus vector.

Adenovirus (Ad) and adeno-associated virus (AAV) have attractive and complementary properties that can be exploited for gene transfer purposes. Ad vectors are probably the most efficient vehicles to deliver foreign genes both in vitro and in vivo. AAV exhibits the unique ability to establish latency by efficiently integrating at a specific locus of human chromosome 19 (AAVS1). Two viral elements are necessary for the integration at AAVS1: Rep68/78 and the inverted terminal repeats (AAV-ITRs). In this study, we report the development of two helper-dependent adenoviral (HD) vectors, one carrying the Rep78 gene, the other an AAV-ITR-flanked transgene. Although Rep proteins have been demonstrated to interfere with Ad replication, HD Rep78 vector was successfully amplified on serial passages in 293CRE4 cells with a yield of 50-100 transducing units per cell. DNA integration at the AAVS1 site also was demonstrated in hepatoma cells coinfected with the HD-expressing Rep78 and with the second HD vector carrying a transgene flanked by AAV-ITRs. The high transduction efficiency, large cloning capacity, and high titer of the HD, combined with the site-specific integration machinery provided by AAV-derived components, make the Ad/AAV hybrid viruses a promising vehicle for gene therapy.

Adenoviridae↗
PubMed1998

Acute promyelocytic leukaemia: epidemiology and risk factors. A report of the GIMEMA Italian archive of adult acute leukaemia. GIMEMA Cooperative Group.

Acute promyelocytic leukaemia (APL) exhibits peculiar epidemiological, clinical, cytogenetic and molecular features, compared to the other acute myeloid leukaemias (AML). Data on epidemiology and occupational risk factors for APL desumed from the GIMEMA archive are reported and compared with those of the other AML. An exploratory case-case study was designed on AML patients from 56 haematology centres in Italy. Overall, 4296 patients older than 15 yr with a new diagnosis of acute leukaemia were recorded between July 1992 and July 1997. Of these, 335 were classified as APL, and 2894 as other AML. The median age of APL patients was 43 compared to 59 yr for the other AML (p < 0.00001). In order to identify peculiar risk factors for APL development, different parameters were compared in the 2 groups. After adjusting by age no significant differences were observed with regard to education, lifetime prevalence of cancer among siblings and previous diseases in the patient's history. Occupational exposure as a possible risk factor for APL showed no increased risk compared to other AML among farmers, builders and leather workers. A significant association was found in electricians (OR=4.4, 95% CI=2.0-9.7) and a weak association was found in wood workers (OR=3.2, 95% CI=0.8-10.8). The proportion of APL with respect to other AML was significantly higher in the north east of Italy compared to the rest of the country (OR=1.7, 95% CI=1.3-2.2). These data confirm the younger age of APL patients compared to the other AML. A possible role of electromagnetic fields is suggested by the higher risk of APL in electrical workers and in the more industrialized areas of the country.

Adolescent↗
PubMed1998

Site-specific integration in mammalian cells mediated by a new hybrid baculovirus-adeno-associated virus vector.

Baculovirus can transiently transduce primary human and rat hepatocytes, as well as a subset of stable cell lines. To prolong transgene expression, we have developed new hybrid vectors which associate key elements from adeno-associated virus (AAV) with the elevated transducing capacity of baculovirus. The hybrid vectors contain a transgene cassette composed of the beta-galactosidase (beta-Gal) reporter gene and the hygromycin resistance (Hygr) gene flanked by the AAV inverted terminal repeats (ITRs), which are necessary for AAV replication and integration in the host genome. Constructs were derived both with and without the AAV rep gene under the p5 and p19 promoters cloned in different positions with respect to the baculovirus polyheidrin promoter. A high-titer preparation of baculovirus-AAV (Bac-AAV) chimeric virus containing the ITR-Hygr-beta-Gal sequence was obtained with insect cells only when the rep gene was placed in an antisense orientation to the polyheidrin promoter. Infection of 293 cells with Bac-AAV virus expressing the rep gene results in a 10- to 50-fold increase in the number of Hygr stable cell clones. Additionally, rep expression determined the localization of the transgene cassette in the aavs1 site in approximately 41% of cases as detected by both Southern blotting and fluorescent in situ hybridization analysis. Moreover, site-specific integration of the ITR-flanked DNA was also detected by PCR amplification of the ITR-aavs1 junction in transduced human fibroblasts. These data indicate that Bac-AAV hybrid vectors can allow permanent, nontoxic gene delivery of DNA constructs for ex vivo treatment of primary human cells.

Animals↗
PubMed1992

Randomized comparison of ceftriaxone versus ceftriaxone plus amikacin for the empirical treatment of infections in patients with altered host defense: microbiological and clinical evaluation.

Two hundred and eighty-four febrile episodes in immunocompromised patients were treated with ceftriaxone alone or in combination with amikacin. In the ceftriaxone-treated group, 60 out of 143 febrile episodes were microbiologically documented, while in the group receiving the combination therapy, there were 32 out of 140 (p = 0.0007). Gram-positive microorganisms were more common than gram-negative ones, accounting for 59 of the 101 isolated bacteria. The ceftriaxone regimen appeared to have a response rate comparable to the combination regimen (73.91 vs. 78.88%). Superinfections occurred under both regimens.

Adult↗
PubMed1992

Comparison of norfloxacin and pefloxacin in the prophylaxis of bacterial infection in neutropenic cancer patients.

In this study the efficacy of norfloxacin and pefloxacin for the antibacterial prophylaxis of granulocytopenia was compared in cancer patients following cytostatic treatment. A total of 136 patients was randomly selected to receive either norfloxacin or pefloxacin. Nineteen patients remained afebrile in the norfloxacin group compared with thirty one in the pefloxacin group (p = 0.045). Twenty four microbiologically documented infections (twelve with and twelve without bacteraemia) occurred in sixty seven patients taking norfloxacin, and twelve in sixty nine patients taking pefloxacin (five with and seven without bacteraemia) (p = 0.015). Only one infection caused by Gram-negative bacilli was observed in the pefloxacin group compared with seven in the norfloxacin group (p = 0.019). In conclusion, both microbiological and clinical results showed pefloxacin to be a better antibacterial agent than norfloxacin for these patients.

Adolescent↗
PubMed1991

Patterns of cytomegalovirus retinitis in immunocompromised patients treated with 9-(2-hydroxy-1-(hydroxymethyl)ethoxymethyl) guanine (ganciclovir).

Five immunocompromised patients, four with AIDS and one who had undergone bone marrow transplantation, showing ocular signs of cytomegalovirus retinitis, were treated with 9-(2-hydroxy-1-(hydroxymethyl)ethoxymethyl) guanine (Ganciclovir), given intravenously at the dose of 5 mg/kg twice daily for a period ranging from 10 to 20 days. At the end of the treatment, in 4 of 5 patients, the ophthalmoscopic picture had improved, with reduced exudation and an arrest in the progression of retinal necrosis, the pattern clearly indicating a trend towards organization and scarring. Complete resolution of the retinitis without subsequent relapse was observed only in the bone marrow transplant patient, who recovered immunologically, whereas improvement of the eye involvement was only transient in the three AIDS patients.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Detection of bacterial contamination in bone marrow graft.

A rapid method of determining bacterial contamination was used in a series of fifty-five bone marrow harvests (20 allogeneic and 35 autologous transplantations). The microbiological culture assays executed on bone marrow samples soon after the harvest and before the manipulation, showed a positivity only in the autologous bone marrow group. Another positivity was revealed after the freezing process of bone marrows for autologous transplantation. Two samples in the bone marrow group submitted to purging were positive after treatment and freezing process. In this study, the increase of bacterial contamination frequency seemed to be related to extensive handlings, such as pharmacological in vitro purging and freezing procedures.

Bacteria↗
PubMed1990

Cytogenetic survey of sixty-one patients with preleukemic syndrome including myeloproliferative and myelodysplastic diseases.

The authors report on a cytogenetic survey of 61 patients with preleukemic syndrome (PLS). Of these, 41 had a myeloproliferative disease (MPD) and 20 a myelodysplastic syndrome (MDS). Clonal chromosome abnormalities appeared in 24 patients (39.3%) at disease onset. Such changes had a frequency of 26.8% in patients with MPD and 65% in those with MDS. The authors stress the usefulness of ethidium bromide high resolution techniques. They allow obtaining a larger number of metaphases and elongated chromosomes with higher banding resolution and could account for the frequent detection of chromosome changes in most groups of MDS patients in the present series. Moreover, they discuss the possible significance of some chromosome aberrations suggesting that patients with MPD may live longer than those with MDS because of their higher frequency of normal karyotypes.

Adult↗