Search PubMed⌕ Search

Biomedical subjects

R Leone

Publications and source records attributed to R Leone.

86 records · Page 5Linked to original sources
PubMedDate not supplied

Active infective endocarditis in infants and childhood: ten-year review of surgical therapy.

We review our 10-year (June 1987-June 1997) experience in 26 children requiring early surgery due to active infective endocarditis (AIE) refractory to medical therapy. Mean age at operation was 5.0 (SD 3.5) years. Nineteen patients (73%) had predisposing factors: congenital heart disease (CHD) was the most common (10/19, 53%); endocavitary foreign materials (6/19); and previous cardiac surgery (3/19). Vegetations or valve dysfunction was detected by transthoracic echocardiography in all cases but one. Valvular location (17/26, 65%) was the most common; others locations included cardiac chambers (8/26) and intravascular thoracic aorta (1/26). Bacterial isolation was achieved in 19 patients (73%): Staphylococcus (10 patients); Streptococcus (6 patients); and Candida albicans (3 patients). The indication for surgery was progressive or persistent cardiac failure (2 patients) or infection (9 patients), or a combination of these (7 patients), despite adequate medical therapy; major embolic accident with a mobile vegetation (4 patients), recurrent pulmonary embolism with a mobile vegetation (3 patients), and mobile vegetation (> 10 mm) in left cardiac chambers (1 patient). All the patients required surgery before 6 weeks of antibiotic therapy had been completed. The hospital mortality was 19% (5/26, 70% confidential limits[CL]: 2-35%). Deaths were due to infective causes in all cases but one. No late deaths occurred in 18 patients followed up for a mean of 4.2 years (SD 2.4). Three patients needed four reoperations. We conclude that improvement in the treatment of children with AIE can be obtained with an early and accurate diagnosis, an adequate antibiotic treatment, and a more aggressive surgical approach.

Child↗
PubMedDate not supplied

Immunoglobulin heavy chain and T-cell receptor beta chain gene rearrangements in acute non lymphoid leukemia.

The occurrence of immunoglobulin heavy chain (IgH) and/or T-cell receptor (TcR) gene rearrangements has been reported in some cases of acute non lymphoid leukemia (ANLL), and variously interpreted as reflecting "aberrant gene expression" or "lineage promiscuity" of the leukemic cell. In an attempt to verify the incidence, FAB distribution and immunophenotypic correlates of gene rearrangements in ANLL, we analyzed the configuration of IgH and TcR beta chain genes in 70 patients with ANLL. In all cases myeloid (CD13, CD33, CD14, CD15) and lymphoid (CD7, CD2, CD10, CD19, TdT) antigenic determinants were analyzed in conjunction with conventional morpho-cytochemical characterization. Clonal rearrangements of the IgH gene were identified in 6/70 ANLL patients (8.6%), whereas in only 2/48 (4.2%) were T beta rearrangements documented. Concerning FAB subtypes, IgH or T beta rearrangements were detected in the less differentiated forms MO and M1 (3 cases), as well as in 2 M4 and 1 M5a cases. With the exception of a higher incidence of gene rearrangements in TdT+ ANLL, no significant correlation was found with other immunophenotypic markers.

Adolescent↗
PubMedDate not supplied

[A new biological irradiator for the laboratory].

The use of high doses (15-20 Gy) of X- or gamma-rays to irradiate blood-derived materials is a common practice by now. It is usual especially when materials must be transfused into non-immunocompetent patients. This is done to avoid the so-called GVH disease. Nowadays, for this purpose, units containing radioactive gamma-emitting sources with high activity and long half-life (usually 137Cs) are on the market. The characteristics of these "irradiators" allow their implementation in any laboratory with no need of structural shieldings. In spite of it, serious accidents (e.g., fire, fallings, etc.) which could imply hazards for the operating staff and even the general population, cannot be excluded. At the same time, the problem of long-term disposal of exhausted sources cannot be neglected. For these reasons, a new type of self-shielded irradiator was designed. It is equipped with an X-ray tube, operating at nearly 200-kV voltage, with 12-mA anodic current. The system is water- and oil-cooled and can work for a long time without thermal overloads. In this paper, the environmental and dosimetric measurements for beam characterization are reported. The system can produce beams with satisfactory characteristics for this specific problem. Moreover, its use may greatly reduce administrative radioprotection problems.

Blood↗