Narcisa Mandras

Antifungal activity of essential oils against filamentous fungi determined by broth microdilution and vapour contact methods

Aims:  The in vitro activity of some essential oils (EO) (thyme red, fennel, clove, pine, sage, lemon balm and lavender) against clinical and environmental fungal strains was determined.

Faecal microbiota in breast-fed infants after antibiotic therapy.

Aim:  To evaluate modifications of gut microbiota after antibiotic therapy in breast‐fed infants.

Comparative Evaluation of the Antimicrobial Efficacy of a 5% Sodium Hypochlorite Subsonic-activated Solution

INTRODUCTION The study evaluated the efficacy of subsonic agitation of sodium hypochlorite (NaOCl) in reducing bacterial load in the root canal. METHODS Root canals of 112 extracted human single-root teeth were preflared using K-Flexofiles (Dentsply Maillefer, Ballaigues, Switzerland) up to #20 and then shaped using ProTaper S1-S2-F1-F2-F3 (Dentsply Maillefer) at the working length. Irrigation was performed with 33 mL of 5% NaOCl, alternating with 10 mL of 10% EDTA. After ethylene oxide sterilization, the root canals were infected with 30 microL of Enterococcus faecalis culture and randomly assigned to four groups (n = 25) of different irrigation regimens plus positive and negative controls. Irrigation was performed with 2 mL of 5% NaOCl. In the NaOCl 15 group, the irrigant was left in place for 15 seconds, and in the NaOCl 30 group it was left in place for 30 seconds. In the EndoActivator (EA; Dentsply Tulsa Dental Specialties, Tulsa, OK) 15 and EA 30 groups, NaOCl was subsonically agitated with EA for 15 and 30 seconds, respectively. The residual bacterial count was then evaluated. Differences among groups were analyzed with one-way analysis of variance and the post hoc Bonferroni test (p < 0.05). RESULTS A statistically significant difference was evidenced among groups (F(3) = 9.01, p < 0.001). The standard irrigation groups (NaOCl 15 and 30) showed higher microbial counts than the EA 30 group (p < 0.05). CONCLUSION Thirty seconds of NaOCl subsonic agitation with EndoActivator appears to be slightly more effective in reducing bacterial load in the root canal compared with NaOCl irrigation alone.

Role of fosfomycin tromethamine in modulating non-specific defence mechanisms in chronic uremic patients towards ESBL-producing Escherichia coli.

Antimicrobial agents and polymorphonuclear cells (PMNs) have the potential to interact in such a way that improve the therapy for infectious diseases. In immunocompromised patients highly susceptible to microbial infections with high morbidity and mortality, several metabolic and functional alterations in PMNs, mostly related to microbicidal activity, are observed. Therefore, the antibiotic of choice should have a good antimicrobial effect without impairing host defences. The aim of this study is to evaluate in vitro effects of sub-inhibiting fosfomycin tromethamine (FT) concentrations on the primary functions of PMNs from healthy subjects and immunocompromised patients (haemodialysed and renal transplant recipients), against an ESBL-producing Escherichia coli, the most common aetiological agent in urinary tract infections (UTIs). FT is considered a first line drug in the eradication of UTIs due to its appropriate antimicrobial spectrum, oral bioavailability and minimal risk of microbial resistance. Our results provide evidence that FT is able to induce enhancement of the depressed phagocytic response of PMNs from patients on chronic haemodialysis and from renal transplant recipients, restoring their primary functions in vitro against ESBL-producing E. coll All these data permit the conclusion that uremic-infected patients might additionally benefit from the immunomodulating properties of FT.

Non-dermatophyte moulds as skin and nail foot mycosis agents: Phoma herbarum, Chaetomium globosum and Microascus cinereus

The increased prevalence of dermatomycoses along with the wide range of organisms now recognized as potential pathogens needs accurate laboratory isolation and identification of the aetiological agents. In this report three cases of foot dermatomycoses due to filamentous fungi commonly present in the environment with ubiquitous distribution are described in immunocompetent subjects. Skin and nail samples were collected, suspended in 20% KOH solution, examined under a light microscope and cultured in Mycobiotic agar and Sabouraud dextrose agar containing chloramphenicol to detect fungal growth. Phoma herbarum, Chaetomium globosum, and Microascus cinereus were isolated and identified.

In Vitro Activities of Fluconazole and Voriconazole against Clinical Isolates of Candida spp. Determined by Disk Diffusion Testing in Turin, Italy

ABSTRACT The in vitro activities of fluconazole and voriconazole against 1,024 clinical isolates of Candida spp. were determined by the agar disk diffusion test using the Clinical and Laboratory Standards Institute (CLSI) M44-A guidelines. The results of this investigation demonstrated the broad-spectrum in vitro activity of voriconazole, relative to that of fluconazole, against yeasts tested, in particular fluconazole-resistant isolates, such as Candida krusei that showed high susceptibility to voriconazole. The situation in Turin, Italy, is quite similar to that of the rest of Italy, reflecting the worldwide trend.

Schizophyllum commune: an unusual of agent bronchopneumonia in an immunocompromised patient

We report a case of bronchopneumonia due to Schizophyllum commune in an immunocompromised patient. While this fungus rarely causes disease in humans, it has been reported in association with several clinical entities and lung disorders. A 59-year-old white man with a gastric carcinoma was admitted to S. Giovanni Battista Hospital (Turin, Italy). Three days after the admission, he developed a bronchopneumonia, which was diagnosed through the use of X-ray and showed an abnormal infiltrative shadow. Samples of bronchial aspirate were collected for laboratory microbiological investigation. Direct microscopic examination of these specimens revealed the presence of numerous septate, hyaline hyphae and rare clamp connections. Sabouraud Dextrose Agar and Columbia agar plus 5% blood media inoculated with portions of the same specimens yielded, after 4-5 days of incubation at 25 degrees C and 37 degrees C, a cottony white mould. The fungus was identified on the basis of its macroscopic and microscopic morphology. The macroscopic examination of the colony showed raised, curved, fan-shaped and shell-like basidiocarps. The microscope examination revealed the presence of hyaline, septate hyphae with clamp connections and short, thin spicules. The fungal isolate was identified as S. commune. The patient was cured after therapy with intravenous fluconazole (600 mg twice daily for over six weeks).

Antimicrobial chitosan nanodroplets: new insights for ultrasound-mediated adjuvant treatment of skin infection

BACKGROUND Chronic wounds, characterized by hypoxia, inflammation and impaired tissue remodeling, are often worsened by bacterial/fungal infections. Intriguingly, chitosan-shelled/decafluoropentane-cored oxygen-loaded nanodroplets (OLNs) have proven effective in delivering oxygen to hypoxic tissues. AIM The present work aimed at investigating nanodroplet antimicrobial properties against methicillin-resistant Staphylococcus aureus (MRSA) or Candida albicans, toxicity on human keratinocytes (HaCaT) and ultrasound (US)-triggered transdermal delivery. MATERIALS & METHODS Nanodroplet antibacterial/antifungal properties, human cytotoxicity, and US-triggered transdermal delivery were measured through microbiological, biochemical, and sonophoresis assays, respectively. RESULTS OLNs and oxygen-free nanodroplets (OFNs) displayed short- or long-term cytostatic activity against MRSA or Candida albicans, respectively. OLNs were not toxic to keratinocytes, whereas OFNs slightly affected cell viability. Complementary US treatment promoted OLN transdermal delivery. CONCLUSION As such, US-activated chitosan-shelled OLNs appear as promising, nonconventional and innovative tools for adjuvant treatment of infected chronic wounds.

Synergistic effect of erythromycin on polymorphonuclear cell antibacterial activity against erythromycin-resistant phenotypes of Streptococcus pyogenes

To evaluate the synergistic activity of erythromycin and human polymorphonuclear cells (PMNs) on the binomial erythromycin-resistant (ERY(R)) Streptococcus pyogenes/host, the phagocytic and bactericidal activities of PMNs against ERY(R) streptococcal strains (cMLS(B), M, and iMLS(B) A, B and C phenotypes) were assessed in the presence of the macrolide. The results showed that when erythromycin, PMNs and streptococci [both erythromycin-sensitive (ERY(S)) and ERY(R)] were simultaneously present in the culture medium, PMN phagocytic activity was similar to that of drug-free controls. In contrast, the results emphasised a significant high increase in intracellular killing by PMNs in the presence of erythromycin not only for ERY(S) streptococci but also for ERY(R)S. pyogenes with high (cMLS(B), iMLS(B) A and iMLS(B) B phenotypes) and moderate (M and iMLS(B) C phenotypes) erythromycin resistance compared with controls without drug. From literature data it emerged that, even if intracellularly concentrated, erythromycin is relatively inactive because of its instability. The results indicate that the enhanced intra-PMN streptococcal killing detected is mainly attributable to PMN bactericidal systems that synergise with intracellular erythromycin in eradicating ERY(R)S. pyogenes strains (both with high and moderate resistance). These data confirm that the antibiotic resistance detected in vitro does not always imply a failure of antimicrobial treatment.

Improvement of clinical response in allergic rhinitis patients treated with an oral immunostimulating bacterial lysate: in vivo immunological effects.

Allergic rhinitis is known to be one of the most common chronic diseases in the industrialized world. According to the concept that allergic rhinitis patients generally suffer from an immune deficit, in order to stimulate specifically or aspecifically their immune system, immunomodulating agents from various sources, such as synthetic compounds, tissue extracts or a mixture of bacterial extracts, have been used. The aim of the present trial is to evaluate the efficacy of the treatment with an immunostimulating vaccine consisting of a polyvalent mechanical bacterial lysate (PMBL) in the prophylaxis of allergic rhinitis and subsequently to analyze its in vivo effects on immune responses. 41 allergic rhinitis patients were enrolled: 26 patients were randomly assigned to the group for PMBL sublingual treatment and 15 others to the group for placebo treatment. For all 26 patients blood samples were drawn just before (T0) and after 3 months of PMBL treatment (T3) to evaluate plasma IgE levels (total and allergen-specific) and the cytokine production involved in the allergic response (IL-4, IFN-γ). The results of our study indicate that PMBL is effective in vivo in the reduction or in the elimination of the symptoms in rhinitis subjects during the treatment period in comparison to a non-immunostimulating treatment. A significant and clinically relevant improvement was found in 61.5%, a stationary clinical response was registered in 38.4% and no negative side effects associated with the medication or worsening were recorded. At the end of a 3-month follow up period the clinical picture remained the same as that observed at T3. PMBL treatment did not affect the serum IgE levels (either total or allergen-specific) and did not induce significant changes in IFN-γ concentration. In contrast, PMBL therapy may be accompanied, in some patients, by a potential immunomodulating activity by decreasing IL-4 cytokine expression.