Publications by authors named "Perversi L"

Following the identification of two clinical isolates of vancomycin-resistant enterococci (VRE) from intensive care unit (ICU) patients, a surveillance programme detected that six of eight ICU patients were colonised by VRE. Standard epidemic control measures were instituted in the ICU. During a 16-month period, 13 (2.

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Probiotic microorganisms to be used as biotherapeutic agents have to resist the rigors of the upper human gastrointestinal tract. In this study we evaluated the acid tolerance in vitro and the fecal recovery in vivo after oral administration of a Saccharomyces cerevisiae strain to healthy volunteers. At the lowest pH value (pH 1.

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In this study we evaluated the antibacterial activity of mastic gum, a resin obtained from the Pistacia lentiscus tree, against clinical isolates of Helicobacter pylori. The minimal bactericidal concentrations (MBCs) were obtained by a microdilution assay. Mastic gum killed 50% of the strains tested at a concentration of 125 microg/ml and 90% at a concentration of 500 microg/ml.

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Background And Objectives: The emergence of vancomycin-resistant enterococci (VRE) as nosocomial pathogens is a major problem in the US; in Europe, VRE nosocomial infections are uncommon and only rarely have been reported in Pediatric or Neonatal Units. The aim of this study is to report on the clinical and microbiological features of VRE infections in 3 children given hematopoietic stem cell transplantation (HSCT).

Patients And Methods: Five episodes of vancomycin-resistant Enterococcus faecium (VREF) infection were diagnosed in 3 children given an allogeneic HSCT.

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To investigate effect of MMLA, an inhibitor of nitric oxide (NO) production, on regulation of inflammatory responses to Bordetella pertussis infection, mice were infected intranasally, and treated with various concentrations of MMLA. Ten days after infection, mice treated with MMLA at dosage of 100 mg/kg, given intraperitoneally in a single dose or for 5 consecutive days, showed at histopathologic examination, a significant decrease of intensity of inflammation (scores, 0.6 +/- 0.

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Silver sulfadiazine (SSD), a topical antimicrobial agent, has been widely used for the prophylaxis and treatment of burn infections during the past 30 years. We determined the antimicrobial activity of SSD, alone and in combination with cerium nitrate (CN), gentamicin and amikacin against 130 recent clinical isolates, including multiresistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) or Pseudomonas aeruginosa. The overall activity of SSD was good against all the tested strains and it was particularly high against MRSA (MIC90 100 microg/ml).

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The recombinant cytokines interferon (IFN)-gamma and interleukin (IL)-12 stimulate several macrophage-mediated functions that are important in host defense. An experimental pertussis model showed that intraperitoneal (i.p.

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Nitric oxide (NO) exhibits potent antimicrobial activity in vitro. The function of NO in host defenses in vivo, however, is presently unclear. Experiments were undertaken to determine the production of NO in vitro from murine peritoneal and alveolar macrophages, and murine macrophage cell line (J774A.

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The in vitro antibacterial activity of ofloxacin, sagamycin and other antibiotics was evaluated against 85 bacterial isolates [coagulase-negative staphylococci (CNS), n = 37, Staphylococcus aureus, n = 28, and Pseudomonas aeruginosa, n = 20] obtained from patients with ocular infections. The antistaphylococcal activity of ofloxacin was quite elevated with a 90% minimal inhibitory concentration (MIC90) of 1.56 mg/l against CNS and S.

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Several studies have demonstrated that Bordetella pertussis has the ability to enter and survive intracellularly within human polymorphonuclear leukocytes (PMNL) and human monocytes/macrophages. The effects of human recombinant gamma interferon (IFN-gamma) on the survival of B. pertussis in PMNL and human monocytes, and on the oxidative burst activity of PMNL and human monocytes in response to B.

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We compared the in vitro activity of daptomycin, a new lipopeptide antibiotic, with that of vancomycin and other selected agents against 95 coagulase negative staphylococci (CNS) isolates causing septicemia or foreign-body infections in immunocompromised patients. These strains were classified as follows: 51 methicillin-susceptible CNS (23 slime producers); 44 methicillin-resistant CNS (23 slime producers). We also investigated the activity of daptomycin against 50 Enterococcus faecalis isolates.

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The adherence of Bordetella pertussis to respiratory cilia and its survival in neutrophils and macrophages is crucial to the pathogenesis of whooping cough. To investigate the role of endogenous interferon (IFN)-gamma in acute infection, levels of IFN-gamma in bronchoalveolar lavage (BAL) fluid of mice infected intranasally with B. pertussis were determined.

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Morphological changes induced by teicoplanin and vancomycin on Staphylococcus aureus have been comparatively evaluated. The most pronounced structural damages were found on the cell wall which was uniformly thickened on bacteria exposed to teicoplanin while it was of irregular thickness and often absent around the cells in those exposed to vancomycin. The inhibitory action of teicoplanin on proteoglycan polymerization but not on nucleic acid and protein synthesis indicates that the effect in the wall is due to the accumulation at this level of proteoglycan soluble precursors continuously produced by the cell.

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The beneficial effect of disaccharides, lactulose and lactitol, in prevention and treatment of hepatic encephalopathy is well established but their use in combination with neomycin is still controversial. We studied in vitro the fecal bacterial growth, acid and gas formation in presence of lactitol (beta-galactoside-sorbitol) and neomycin alone or in combination. The results indicate that neomycin only inhibits the growth of susceptible bacteria (E.

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Co-trimoxazole or norfloxacin were randomly administered to 44 granulocytopenic children with malignancies in order to prevent bacterial infections. Although more patients in the co-trimoxazole group had febrile episodes (p less than 0.01), the mean of febrile days and the mean of days with systemic antibiotics did not differ significantly in the two groups.

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In this study we report about the efficacy and tolerability of ofloxacin in the treatment of 15 patients with severe and moderately severe infections including osteomyelitis (5), soft tissue infections (5), salmonellosis in AIDS patients (2), acute or chronic pulmonary infections (2) and mediastinitis (1). The following organisms were isolated in culture specimens: Staphylococcus aureus (4), Pseudomonas aeruginosa (4), Staphylococcus epidermidis (3), Serratia marcescens (1), Escherichia coli (1), Aeromonas hydrophila (1), Klebsiella oxytoca (1), Klebsiella pneumoniae (1), Salmonella cholerae-suis (1), Salmonella sp. (1), Enterobacter cloacae (1).

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The in vitro activity of antibiotic combination of teicoplanin and gentamicin (or netilmicin) and teicoplanin and cephalotin on Staphylococcus aureus was evaluated using the checkerboard method and time-kill curves. With few exceptions neither antagonism nor synergism was seen for the combination of teicoplanin and aminoglycosides using the checkerboard method. Using time-kill curves synergism was often found for the combination of teicoplanin and netilmicin (even at sub-minimal inhibitory concentrations of netilmicin) and for the combination of teicoplanin and cephalotin.

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Resistance of Enterobacter, Serratia and pseudomonas strains to newer cephalosporins is often associated with stable derepression of synthesis of the chromosomal betalactamases. Similar resistance is developed by enzyme inducible strains in response to betalactamases inducers. This finding poses many clinical problems including emergence of resistance during therapy with the drugs.

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