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G Scalise

Publications and source records attributed to G Scalise.

At least 109 records · Page 6Linked to original sources
PubMed1994

Imipenem and meropenem induced resistance to beta-lactam antibiotics in Pseudomonas aeruginosa.

The ability of imipenem and meropenem in subinhibitory concentrations to influence the results of disk diffusion susceptibility tests was assessed. Selection of stably derepressed mutants resistant to beta-lactam antibiotics other than carbapenems was also investigated. Beta-lactams were shown to be subject to carbapenem-mediated antagonism in the disk diffusion test. On the other hand in vitro selection of stably derepressed mutants resistant to other beta-lactams could not be demonstrated.

Anti-Bacterial Agents↗
PubMed1994

Comparison of broth dilution and semisolid agar dilution for in vitro susceptibility testing of Cryptococcus neoformans.

We compared the in vitro activity of amphotericin B, flucytosine, itraconazole, fluconazole, ketoconazole and miconazole against 18 strains of Cryptococcus neoformans by using two methods: microbroth dilution and semisolid agar dilution. By both of the methods minimum inhibitory concentrations (MICs) showed a wide range for all antifungal agents but not for amphotericin B. Statistically significant differences between the two methods were observed only with amphotericin B and flucytosine, p = 0.048 and p = 0.045 respectively. Our study suggests that azole susceptibility testing for C. neoformans may be performed by the broth microdilution as well as the semisolid agar test. The choice of the method when testing amphotericin B and flucytosine is more problematic.

Amphotericin B↗
PubMed1994

Bacteriostatic and bactericidal activities of paromomycin against Mycobacterium avium complex isolates.

The MICs and MBCs of paromomycin for 32 Mycobacterium avium complex (MAC) strains isolated from patients with the acquired immunodeficiency syndrome were determined by a radiometric broth dilution method. The MICs for the majority of strains were either 8 or 16 mg/L and the MBCs were four- to eight-fold higher. Paromomycin merits further evaluation as oral prophylaxis against disseminated MAC infection.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Dynamics of molecular parameters of human immunodeficiency virus type 1 activity in vivo.

The dynamics of viral activity during different phases of human immunodeficiency virus type 1 (HIV-1) infection were investigated by competitive PCR methods. In particular, we studied the time course of three quantitative molecular parameters of viral activity (genomic RNA copy number in plasma and provirus and late HIV-1 transcript molecule copy numbers in peripheral blood CD4+ T lymphocytes) in untreated patients and patients treated with specific anti-HIV-1 compounds. The results shown here indicate that direct RNA parameters are quantitative molecular indices sensitive enough to be used for a more accurate evaluation of the natural history of this infection and that an indirect parameter, the mean transcriptional activity for each provirus in CD4+ T lymphocytes, may be important in studying this infection in vivo at the molecular level. A dramatic decrease of the indices was evident at seroconversion, but the quantitative values were virtually stable throughout the time the untreated patients were studied during the clinical latency phase. Furthermore, the results indicate that an early response to antiretroviral compounds is detected in most subjects as a decrease in the viral activity level.

Acquired Immunodeficiency Syndrome↗
PubMed1993

Turbidimetric and visual criteria for determining the in vitro activity of six antifungal agents against Candida spp. and Cryptococcus neoformans.

The drug concentration which inhibited 50% of growth (IC50), the lowest drug concentration at which growth was less than 30% of that in a positive control well (IC30), the visual minimal inhibitory concentration (MIC), and the minimum fungicidal concentration (MFC), were applied to study the effects of fluconazole, itraconazole, ketoconazole, miconazole, flucytosine, and amphotericin B against 36 isolates of Candida spp. and Cryptococcus neoformans by a broth microdilution technique. When the recommendations established by the NCCLS Subcommittee on Antifungal Susceptibility Tests were applied for the visual reading of the microplates, the results were comparable with those obtained by the turbidimetric methods. Differences between MICs and IC30s were observed with miconazole against strains of C. glabrata (p = 0.014) and with flucytosine against strains of C. neoformans (p = 0.041). Differences between MICs and IC50s were observed with fluconazole against strains of C. albicans (p = 0.027), C. tropicalis (p = 0.046), and C. neoformans (p = 0.041); with miconazole against strains of C. glabrata (p = 0.014); and with amphotericin B against strains of C. parapsilosis (p = 0.025). Ten additional isolates of C. albicans from AIDS patients suffering from recurrent episodes of oral candidiasis and clinically resistant to fluconazole also were included in this study. The MICs of fluconazole of these strains were significantly higher than those of the control group (p = 0.003). When the turbidimetric parameters were applied for testing the in vitro activity of fluconazole against the above isolates, both IC30 and IC50 were capable of discriminating the strains of the two groups (p = 0.002, p = 0.001, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS-Related Opportunistic Infections↗
PubMed1993

Characterization of mesophilic Aeromonas from clinical specimens by computerized analysis of SDS-PAGE protein profiles and by enzymatic activity.

Mesophilic Aeromonas (Aeromonas hydrophila, Aeromonas sobria, Aeromonas caviae) have recently been considered important aetiological agents of human diseases, mainly gastrointestinal infections. Although several findings have pointed out the significance of this group of microorganisms as enteric pathogens and suggested the presence of virulence factors, epidemiological and clinical studies are limited by the difficulty of correctly identifying mesophilic Aeromonas at the species level. SDS-PAGE of radiolabelled total protein profiles and bacterial enzymatic activities were used to type 31 clinical isolates (6 A. hydrophila, 7 A. sobria and 18 A. caviae) from patients with gastroenteritis and from healthy controls. Analysis of SDS-PAGE protein patterns, reinforced by the UPGMA-grouping system (AMBIS software) provided a good characterization of A. caviae strains as a homogeneous group of microorganisms, possessing significant differences from the other two species of mesophilic Aeromonas, in good agreement with biochemical and enzymatic tests. Data obtained in analyzing A. sobria protein profiles clearly showed two groups, with a correlation coefficient (CC) = 0.70, which in our experience is a doubtful value for assigning two strains to the same species. Strains biochemically identified as A. hydrophila showed a CC = 0.64, which is equally not acceptable for species assignment. Inter-species comparison highlighted this heterogeneity, showing two mixed subgroups, both containing strains that were assigned to A. sobria and A. hydrophila species on the basis of biochemical features.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Comparative evaluation of the MB-Check system for recovery of mycobacteria from clinical specimens.

The performance of the MB-Check system (Roche) in the recovery of mycobacteria from clinical specimens was compared with that of the Bactec radiometric system and conventional culture on Löwenstein-Jensen medium. A total of 1,582 clinical specimens were used for the study; 74 yielded mycobacteria. Organisms of the Mycobacterium tuberculosis and Mycobacterium avium complexes accounted for the majority of isolates. The rate of recovery of all mycobacteria with the Bactec system was 91.9%, with the MB-Check system 79.7% and on Löwenstein-Jensen medium only 54.1%. Combination of the Bactec and MB-Check systems allowed recovery of 100% of isolates. The Bactec system showed a faster detection time than the other two methods.

Bacteriological Techniques↗
PubMed1992

Fluconazole and ketoconazole in the treatment of oral and esophageal candidiasis in AIDS patients.

In our study 77 AIDS patients suffering from oral and/or esophageal candidiasis were evaluated: 38 received fluconazole, 39 ketoconazole. We analyzed the rates of clinical and mycological responses, relapses and toxicities. In vitro susceptibility tests for both antifungal drugs were performed by evaluating their Minimal Inhibitory Concentrations (MICs). The azole drugs investigated show a good activity in the treatment of oropharyngeal and esophageal candidiasis also in advanced stages of HIV infection. Clinical cure or improvement were achieved in 29 (76.3%) and 31 (79.4%) of the patients treated with fluconazole or ketoconazole respectively. Clinical or laboratory adverse experiences related to fluconazole were seen in 7 (21.2%) patients while ketoconazole provoked adverse experiences in 9 (26.4%) patients. In vitro susceptibility tests, if repeated more than once, both in primary infection and relapses, could be important to demonstrate a probable sensitivity change or resistance of the tested strains.

AIDS-Related Opportunistic Infections↗
PubMed1992

Nonmycetomic Actinomadura madurae infection in a patient with AIDS.

Actinomadura madurae is an aerobic actinomycete which is best known worldwide as the cause of actinomycotic mycetomas. It has not previously been reported to have caused invasive pulmonary or disseminated infection in humans. We describe an AIDS patient with opportunistic A. madurae-induced pneumonia and bacteremia. The isolate from the patient's blood was subjected to dilutional antimicrobial susceptibility tests with 12 antimicrobial agents and was found to have a wide spectrum of susceptibility. This unusual microorganism may be a cause of infections in severely immunosuppressed patients.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Molecular profile of human immunodeficiency virus type 1 infection in symptomless patients and in patients with AIDS.

Recent molecular evidence indicates that active human immunodeficiency virus type 1 (HIV-1) infection is detectable in both symptomless and symptomatic infected patients. For this main reason, it has been pointed out that precise quantitative analysis of viral activity in vivo is necessary, firstly, for the pathogenetic investigation of the steps relevant to infection progression and, secondly, for better clinical management of HIV-1-infected patients. In this study, the presence of HIV-1 genomic RNA in plasma samples, specific HIV-1 transcripts in peripheral blood mononuclear cells, and proviral DNA sequences were assayed for 33 HIV-1-infected patients (including symptomless and symptomatic subjects) by using a competitive polymerase chain reaction method that allows quantitation of the RNA/DNA target sequences. The quantitative results obtained confirm that transcription of HIV-1 structural genes and complete viral replication occur in all the HIV-1-infected patients independently of the clinical stage. However, although sharp individual differences were detected, a high degree of correlation of the molecular parameters studied with both disease progression and a decrease in the number of CD4+ T lymphocytes was documented. Interestingly, despite the increasing viremia level associated with infection progression, the mean transcriptional activity of individual infected cells was found to be only moderately greater in AIDS patients than in asymptomatic infected subjects. In addition, it was noted that quantitation of HIV-1 genomic RNA in plasma samples and quantitation of specific HIV-1 transcripts in peripheral blood mononuclear cells appear to be more reliable and sensitive markers of viral activity than quantitative analysis of proviral HIV-1 sequences in peripheral lymphocytes.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Viral hepatitis: modern aspects of clinical diagnosis.

In these years, more light has been brought into the field of hepatitis viruses, particularly with regard to their biology and etiopathogenesis. Besides, first attempts of specific therapy have been done, thanks to the introduction of interferons. This paper wants to give the main guidelines of up-to-date diagnosis and treatment of hepatitis supported by viral infection.

Biomarkers↗
PubMed1992

In vitro activity of the new quinolone lomefloxacin against Mycobacterium tuberculosis.

Minimal inhibitory concentrations (MIC) of ciprofloxacin, ofloxacin and lomefloxacin were determined for 90 Mycobacterium tuberculosis strains isolated from both AIDS and other patients. Eleven (12.2%) of these strains showed in vitro resistance to one or more first-line antituberculosis drugs. Susceptibility tests were done in 7H12 broth by the radiometric method. The MIC range for ciprofloxacin was 0.125 to 4.0 micrograms/ml; for ofloxacin, 0.25 to 4.0; and for lomefloxacin 0.5 to 4.0 micrograms/ml. On the basis of our data, we believe that the following MIC, when determined in 7H12 broth radiometrically, should be used as break points to classify the strain as susceptible: ciprofloxacin and ofloxacin, 1 microgram/ml or less; lomefloxacin, 2 micrograms/ml or less. Lomefloxacin on a once-daily basis deserves further evaluation as a potential supplementary drug for the treatment of tuberculosis.

Anti-Infective Agents↗