Antifungal and anti-biofilm activity of the first cryptic antimicrobial peptide from an archaeal protein against Candida spp. clinical isolates

Candida species cause cutaneous and systemic infections with a high mortality rate, especially in immunocompromised patients. The emergence of resistance to the most common antifungal drugs, also due to bioflm formation, requires the development of alternative antifungal agents. The antimicrobial peptide VLL-28, isolated from an archaeal transcription factor, shows comparable antifungal activity against 10 clinical isolates of Candida spp. Using a fuoresceinated derivative of this peptide, we found that VLL-28 binds to the surface of planktonic cells. This observation suggested that it could exert its antifungal activity by damaging the cell wall. In addition, analyses performed on bioflms via confocal microscopy revealed that VLL-28 is diferentially active on all the strains tested, with C. albicans and C. parapsilosis being the most sensitive ones. Notably, VLL-28 is the frst example of an archaeal antimicrobial peptide that is active towards Candida spp. Thus, this points to archaeal microorganisms as a possible reservoir of novel antifungal agent

Anti-Invasive Activity of Bovine Lactoferrin against Listeria monocytogenes.

We have investigated the possible role of bovine lactoferrin in protecting the intestinal epithelium from bacterial infections, using as an in vitro model enterocyte-like cell lines HT-39 and Caco-2 infected with a food-borne pathogen, Listeria monocytogenes . When infection occurred in the presence of 1 mg/ml of bovine lactoferrin, in the form of apolactoferrin or iron- or manganese-saturated forms, the adhesion of bacteria to eukaryotk cells was unaffected, but the number of internalized bacteria was reduced by 42- to 125-fold. The possibility of a toxic effect of lactoferrin was excluded, because bovine lactoferrin was used at nonbactericidal and noncytotoxic concentrations

Early ultrasonographic finding of septic thrombophlebitis is the main indicator of central venous catheter removal to reduce infection-related mortality in neutropenic patients with bloodstream infection.

BACKGROUND: Septic thrombophlebitis increases patient morbidity and mortality following metastatic infections, pulmonary emboli, and/or septic shock. Central venous catheter (CVC) removal for occult septic thrombophlebitis challenges current strategy in neutropenic patients. PATIENTS AND METHODS: We prospectively evaluated infection-related mortality in 100 acute leukemia patients, with CVC-related bloodstream infection (CRBSI) after chemotherapy, who systematically underwent ultrasonography to identify the need for catheter removal. Their infection-related mortality was compared with that of a historical cohort of 100 acute leukemia patients, with CRBSI after chemotherapy, managed with a clinically driven strategy. Appropriate antimicrobial therapy was administered in all patients analyzed. RESULTS: In the prospective series, 30/100 patients required catheter removal for ultrasonography-detected septic thrombophlebitis after 1 median day from BSI onset; 70/100 patients without septic thrombophlebitis retained their CVC. In the historical cohort, 60/100 patients removed the catheter (persistent fever, 40 patients; persistent BSI, 10 patients; or clinically manifest septic thrombophlebitis, 10 patients) after 8 median days from BSI onset; 40/100 patients retained the CVC because they had not clinical findings of complicated infection. At 30 days median follow-up, one patient died for infection in the ultrasonography-assisted group versus 17 patients in the historical cohort (P < 0.01). With the ultrasonography-driven strategy, early septic thrombophlebitis detection and prompt CVC removal decrease infection-related mortality, whereas clinically driven strategy leads to inappropriate number, reasons, and timeliness of CVC removal. CONCLUSION: Ultrasonography is an easy imaging diagnostic tool enabling effective and safe management of patients with acute leukemia and CRBSI

Rapid and reliable MALDI-TOF mass spectrometry identification of Candida non-albicans isolates from bloodstream infections

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In Vitro Resistance to Macrolides and Clindamycin by Group B Streptococcus Isolated from Pregnant and Nonpregnant Women

Background. Despite the introduction of screening bases intrapartum prophylaxis, Streptococcus agalactiae is still an important etiological agent of perinatal infections. The increasing rate of resistance and the differences in resistance pattern among countries suggest that a program of surveillance at the institutional level is important in determining optimal prophylaxis. In contrast, knowledge on GBS epidemiology in Italy is limited, and no data are available in the Southern region of the country. We sought to determine the occurrence of resistance to macrolides and clindamycin of GBS isolates in pregnant and nonpregnant women. Methods. Between 2005 and 2008, 1346 vaginal and 810 rectovaginal swabs were obtained from pregnant and not-pregnant women. Results. The occurrence of macrolides and clindamycin resistance was 16.5% in 2005 increasing up to 69.9% in 2008. A high percentage of isolates was resistant to tetracycline through all the study period with no statistically significant annual. Conclusions. In our cohort, an increase of in vitro resistance of GBS to macrolides and clindamycin is clearly evident. The discordance with reports from different countries emphasize the crucial role of microbiological methods in setting possible therapeutic strategies

Chemical Composition of Aspergillus creber Extract and Evaluation of its Antimicrobial and Antioxidant Activities

Among the species belonging to the Aspergillus section Versicolores, Aspergillus creber has been poorly studied and still unexplored for its biological activities. The present study was undertaken to analyze A. creber extract and to evaluate its in vitro antimicrobial and antioxidant activities. UHPLC-MS/MS analysis of A. creber extract allowed the characterization of five known fungal metabolites including: asperlactone, emodin, sterigmatocystin, deoxybrevianamide E, and norsolorinic acid. The highest antimicrobial activity was displayed against Candida albicans, with a mean strongest inhibition zone of 20.6 ± 0.8 mm, followed by Gram-positive drug-resistant bacteria. The MIC values of A. creber extract varied from 0.325 mg/ml to 5 mg/ml. A. creber extract was shown a potent antioxidant activity and a high level of phenolic compounds by recording 89.28% scavenging effect for DPPH free radical, 92.93% in ABTS assay, and 85.76 mg gallic acid equivalents/g extract in Folin-Ciocalteu assay. To our knowledge, this is the first study concerning biological and chemical activities of A. creber species. Based on the obtained results, A. creber could be a promising source of natural antimicrobial and antioxidant compounds

Thyroglobulin measurement in the washout of fine needle aspirates for the diagnosis of suspicious cervical lymph nodes

Ultrasound-guided fine-needle aspiration cytology (FNAC) for suspicious cervical lymph nodes (CLN) is the gold standard technique for the identification of metastases from differentiated thyroid carcinomas. Thyroglobulin protein (Tgp) assay in the washout of needles employed for FNA biopsies (FNAB) has been reported to refine and support FNAC performances, especially in cases of inadequate sampling or cystic lymph nodes. In the present work, we evaluated the usefulness of routine measurement of Tgp in the FNAB washout of suspicious cervical lymph nodes (CLN), and its ability to increase the FNAC accuracy in the diagnosis of metastatic CLN. A case study of 45 CLN with histological diagnosis from 36 patients was analyzed. Histology showed metastases from papillary thyroid carcinomas (PTC) in 31 CLN, from anaplastic thyroid cancer (ATC) in 3 CLN, from medullary thyroid cancer (MTC) in 4 CLN, and metastases from extrathyroidal malignancies in 5 CLN. Two CLN analyzed were found to be non-neoplastic. The overall accuracy of FNAC was 82.9%, and that of Tgp was 91.1%, not statistically different. However, Tgp determination was found essential in 4 cases of metastatic CLN from DTC with inadequate cytology, and in 1 case in which the FNAC provided a false negative result. We demonstrated that FNAC and Tgp assay show similar diagnostic accuracies, and that Tgp measurement may represent the only available information in case of inadequate lymph node sampling or cystic lymph nodes

kluyvera ascorbata infection in cystic fibrosis airway disease

Bacilli belonged to genus Kluyvera are Gram negative non-fermentative microorganisms described in the Enterobacteriaceae family, generally considered as saprophytes of the digestive tract.Their role in pathogenesis of infectious disease is unclear, but recently, they are emerged as a cause of clinically significant disease in no-CFpopulation and several anatomic sites are involved as urinary, respiratory and gastrointestinal tracts. In the present note, we describe the identification of Kluyvera ascorbata isolates, obtained from sputum samples of one CF patient (male, 10 years old). The note concerns a patient suffering from chronic obstructive bronchopulmonary disease and chronic Pseudomonas aeruginosa infection. Isolates showed a good growth on MacConkey agar and BCSA, after incubation at 37°C for 24-48 h and they were sensitive to several antibiotics, as cephalosporins, carbapenems, quinolones and trimethoprim-sulfamethoxazole. Clinical observation and the spirometric parameters early before and after isolation of microrganism did not show any worsening status in our patient. The selective pressure given by intensive use of antibiotics in CF patients increases susceptibility to infections by opportunistic microrganisms. Our report underlines the importance of careful bacterial identification and antimicrobial susceptibility study in defining the potential role of new pathogen bacteria in CF lung and to address possible therapeutic strategies that may help to guide antibiotic therapy regimes in CF patients

Protection against Pseudomonas aeruginosa lung infection in mice by recombinant OprF-pulsed dendritic cell immunization

BACKGROUND: The Pseudomonas aeruginosa major constitutive outer membrane porin protein F (OprF) has been shown to be a protective antigen and was previously used to activate an immunological response in a mouse model of lung pneumonia. The purpose of our study was to demonstrate the ability of mouse dendritic cells pulsed with purified or recombinant OprF to protect mice against P. aeruginosa infection and inflammation.Both native (n-OprF), isolated and purified from PAO1 bacterial strain, and recombinant (histidin-conjugated) OprF (His-OprF), obtained by cloning of the oprF gene into the pET28a expression vector, were used to stimulate dendritic cells in vitro before adoptive transfer into prospective recipient mice with P. aeruginosa pulmonary infection. RESULTS: Similar to n-OprF, His-OprF activated dendritic cells in vitro, inducing the costimulatory molecule expression as well as cytokine production. Upon adoptive transfer in vivo, porin-pulsed dendritic cells (DCs) induced Th1-mediated resistance to infection and associated inflammatory pathology caused by either the PAO1 strain or a clinically-isolated mucoid strain. CONCLUSIONS: This study highlights the pivotal contribution of DCs to vaccine-induced protection against P. aeruginosa infection and associated inflammation