A comparison of two blood culture procedures for the isolation of staphylococci in a paediatric intensive care unit.

Blood culture results obtained between January 2000 and July 2003 were reviewed for 1360 patients in a paediatric intensive care unit (PICU). The BacT/Alert FA aerobic medium was used with a blood volume of 1.5 mL for the first 23 months, and the BacT/Alert PF paediatric medium was used with a 0.5-mL volume for the remaining 18 months. The isolation rates were similar during both periods (13.4% vs. 13.1%), and staphylococci were the most common isolates (72.8%). There was a shorter time to detection of staphylococci with the smaller-volume (PF) procedure, which thus seems suitable for use in the diagnosis of staphylococcal bacteraemia in the PICU.

Retinochoroiditis associated with congenital toxoplasmosis in children: IgG antibody profiles demonstrating the synthesis of local antibodies.

PURPOSE: Retinochoroiditis is generally diagnosed after the first year of life and the association with congenital toxoplasmosis presents a diagnostic dilemma. The detection of local intraocular specific antibodies could be useful for diagnosis. METHODS: We studied six patients (mean age 7 +/- 5 years) with retinochoroiditis which appeared after the first year of life. Aqueous and serum were analysed by immunoblotting for anti T. gondii IgG to diagnose toxoplasmosis. RESULTS: All serum samples were positive only for anti T. gondii IgG. The retinochoroiditis was active in three patients and inactive in the others. Immunoblot analysis of serum and aqueous from the patients with active lesions showed IgG versus the specific antigen of T. gondii. In the patients with inactive lesions the pattern was the same in the two compartments. In active forms, aqueous and serum Western blot patterns differed in proteins lower than 16kDa and higher than 116kDa: in aqueous the findings were typically positive for 30kDa. CONCLUSIONS: Aqueous humour analysis by the Western blot technique may be useful in the diagnosis of congenital toxoplasmosis. In the present small series, we nevertheless detected different patterns for inactive and active retinochoroiditis, confirming the diagnosis in the latter. Aqueous humour paracentesis may be indicated in a child with active retinochoroiditis with unusual clinical features, appearing after the first year of life, and with no clinical or serological evidence of congenital infection.

Prostaglandin E(1)-based vasoactive cocktails in erectile dysfunction: how environmental conditions affect PGE(1) efficacy.

INTRODUCTION: The chemical stability of prostaglandin E(1) (PGE(1)) in physiological solution has been studied in different environmental conditions. However, very little data exist regarding the PGE(1) stability and the consequent breakdown products in PGE(1)-based vasoactive cocktails under different environmental conditions. OBJECTIVE: To evaluate the loss of the therapeutic efficacy of PGE(1) either alone or in combination with other vasoactive substances under different storage conditions. MATERIALS AND METHODS: Utilizing high performance liquid chromatography the PGE(1) content was evaluated alone and in association with papaverine and papaverine plus phentolamine at temperatures of 2-8 and at 20 degrees C, and after 15, 30, 60, 90 and 120 days of storage using multivariate statistical analysis of variance. RESULTS: We found that the time of storage significantly affects PGE(1) activity. Furthermore, both the storage temperature and cocktail composition had a significant effect on PGE(1) stability. The chromatographic studies did not disclose the presence of the principal degradation products of PGE(1) (PGA(1), PGB(1)). The presence of papaverine and temperature of 20 degrees C have the greatest effect on the degradation of PGE(1 )during the first 30 days of storage. DISCUSSION: Temperature and time are prevalent factors determining the slow and progressive deterioration curve of PGE(1) after 30 days of storage. None of the environmental conditions evaluated was so drastic to determine the presence of PGA(1) and PGB(1). CONCLUSION: For clinical use, one should note that PGE(1) maintains 50-80% of its efficacy for about 1 month even if stored at room temperature (20 degrees C) and/or combined with papaverine.

Italian urological manpower: employment prospects and future scenarios. A panorama of employment opportunities for young urologists.

INTRODUCTION: Italy delayed limiting access to the Faculty of Medicine and the reform of schools of specialization was not accompanied by programming the number of scholarships, so employment expectations are often disappointing. The aim of this study is to analyze the employment prospects of specialists in urology through the development of possible scenarios for the 5-year period 2000-2004. MATERIALS AND METHODS: We recorded data received from Italian Schools of Specialization in Urology on specialists in the 5-year period 1994-1998. We also tried to obtain a picture of the national distribution of urologists and urological units. Statistical processing was done with SPSS for Windows 5.0. RESULTS: In the last 5 years, 501 urologists were licensed at an average age of 37 years; 535 urological units exist; 2,332 doctors practice urology (2,235 males and 97 females) for a ratio of 1 urologist to 24,500 inhabitants. By comparing the 'entrance' forecast with the potential 'exit', we can hypothesize an annual excess of 80 units. There is no significant correlation between the number of urologists in each structure and the number of inhabitants for each urologist. CONCLUSIONS: The present government programme does not take into account continual changes in employment and many other variables when defining the actual need for specialists. For valid predictions, the data we obtain must be updated for at least 5 years.

DNA damage and cytotoxicity induced by beta-lapachone: relation to poly(ADP-ribose) polymerase inhibition.

beta-Lapachone (3,4-dihydro-2,2-dimethyl-2H-naphtho[1,2-b]pyran-5, 6-dione) was previously shown to enhance the lethality of X-rays and radiomimetic agents and its radiosensitizing role in mammalian cells was attributed to a possible interference with topoisomerase I activity. Furthermore, beta-lapachone alone was found to induce chromosomal damage in Chinese hamster ovary (CHO) cells. The aim of the present study was to further elucidate the possible mechanisms by which beta-lapachone exerts its genotoxic action in cultured mammalian cells. Flow cytometry analysis of beta-lapachone-treated CHO cells indicated a selective cytotoxic effect upon S phase of the cell cycle. beta-lapachone produced DNA strand breaks as determined by alkaline elution assay; alkaline elution profiles from treated cells showed a bimodal dose-response pattern, with a threshold dose above which a massive dose-independent DNA degradation was observed. Furthermore, beta-lapachone increased the capacity of crude CHO cellular extracts to unwind supercoiled plasmid DNA, while significantly inhibiting in vitro poly(ADP-ribose) polymerase (PARP). These results suggest that damage induction is probably mediated by the interaction between beta-lapachone and cellular enzymatic function(s), rather than reflecting a direct action on the DNA. We suggest that the inhibition of PARP plays a central role in the complex biological effects induced by beta-lapachone in CHO cells.

Low environmental radiation background impairs biological defence of the yeast Saccharomyces cerevisiae to chemical radiomimetic agents.

Background radiation is likely to constitute one of the factors involved in biological evolution since radiations are able to affect biological processes. Therefore, it is possible to hypothesize that organisms are adapted to environmental background radiation and that this adaptation could increase their ability to respond to the harmful effects of ionizing radiations. In fact, adaptive responses to alkylating agents and to low doses of ionizing radiation have been found in many organisms. In order to test for effects of adaptation, cell susceptibility to treatments with high doses of radiomimetic chemical agents has been studied by growing them in a reduced environmental radiation background. The experiment has been performed by culturing yeast cells (Saccharomyces cerevisiae D7) in parallel in a standard background environment and in the underground Gran Sasso National Laboratory, with reduced environmental background radiation. After a conditioning period, yeast cells were exposed to recombinogenic doses of methyl methanesulfonate. The yeast cells grown in the Gran Sasso Laboratory showed a higher frequency of radiomimetic induced recombination as compared to those grown in the standard environment. This suggests that environmental radiation may act as a conditioning agent.

Liquid competition radioimmunoassay for the detection and quantitation of the HIV p24.

Productive infection of permissive cell cultures by HIV has been detected by different assays of which the measurement of reverse transcriptase (RT) activity has been considered highly specific and sensitive. Here we describe the production and characterization of a mouse hybridoma cell line, MB12, secreting monoclonal antibodies to HIV p24, the major core protein, and the use of this monoclonal antibody to develop a type specific indirect liquid competitive radioimmunoassay (RIA) capable of providing earlier detection of the replicating virus than the RT assay. This assay also provides a quantitative analysis of HIV p24, which can be used to study the viral replication in permissive cell cultures. The ease of methodology and the adaptability of the competitive RIA to various assay conditions make this immunoassay suitable for the study of HIV expression in infected cell cultures.

Kinetics of erythroid precursors in mice infected with the anemic or the polycythemic strain of Friend leukemia virus.

The kinetics of both erythroid burst-forming and colony-forming units (BFU-E, CFU-E) and myelomonocytic precursors [myelomacrophage colony-forming unit (CFU-C)] have been evaluated in tibial marrow, peripheral blood, and spleen of DBA/2 mice at time intervals after inoculation of either the anemic (FLV-A) or the polycythemic (FLV-P) strain of Friend leukemia virus. Either one of the viruses induced, at 7-10 days after infection, a massive increase in the number of BFU-Es in peripheral blood, in parallel with their depletion in tibial marrow and increase in spleen. A comparable increase in the blood BFU-E number was observed in splenectomized FLV-infected mice. These results indicate a marrow-spleen migration of BFU-Es. In spleen, the increase of the BFU-E number was associated with an increase in the CFU-E pool. In tibial marrow, a sequence of expansion/depletion waves occurred reciprocally at the level of BFU-E and CFU-E. The cycling of BFU-E([(3)H]thymidine in vitro suicide index) in marrow, blood, and spleen was enhanced, whereas that of CFU-E and CFU-C showed little or no modification. These kinetic data suggest that the main target cell of FLV may be the BFU-E or a closely related element. In plates without added erythropoietin (but containing it in fetal calf serum), expression of CFU-E from FLV-P-treated animals was maximal; that of CFU-E from FLV-A-injected mice was either virtually absent or only slight in marrow or spleen, respectively. BFU-E growth always was fully dependent upon erythropoietin addition. Control studies in FLV-infected resistant mice and in susceptible mice given diluted or heat-inactivated virus provide convincing evidence that the phenomena described are induced by FLV.