Experimental Animal Models for Aging Units

Ancona, Italy

Experimental Animal Models for Aging Units

Ancona, Italy
SEARCH FILTERS
Time filter
Source Type

Cirioni O.,Marche Polytechnic University | Mocchegiani F.,Marche Polytechnic University | Cacciatore I.,University of Chieti Pescara | Vecchiet J.,University of Chieti Pescara | And 9 more authors.
Peptides | Year: 2013

The aim of the study was to investigate the efficacy of the quorum sensing inhibitor FS3 and daptomycin in preventing prosthesis biofilm in a rat model of staphylococcal vascular graft infection. Graft infections were established in the back subcutaneous tissue of adult male Wistar rats by implantation of Dacron prostheses followed by topical inoculation with 2 × 107 colony-forming units of Staphylococcus aureus, strain Smith diffuse. The study included a control group, a contaminated group that did not receive any antibiotic prophylaxis and three contaminated groups that received: (i) intraperitoneal daptomycin, (ii) FS3-soacked graft, and (iii) daptomycin plus FS3-soaked graft, respectively. Each group included 15 animals. The infection burden was evaluated by using sonication and quantitative agar culture. Moreover, an in vitro binding-study was performed to quantify the how much FS3 was coated to the surface of the prosthesis. The in vitro studies showed, that minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for daptomycin were lower in presence of FS3. In in vivo studies, when tested alone, daptomycin and FS3 showed good efficacies. Their combination showed efficacies significantly higher than that of each single compound. Daptomycin is an important candidate for prevention of staphylococcal biofilm related infection and FS3 could serve as an interesting anti-staphylococcal antibiotic enhancer. © 2013 Elsevier Inc. All rights reserved.


PubMed | Experimental Animal Models for Aging Units, Marche Polytechnic University and University of Chieti Pescara
Type: Journal Article | Journal: PloS one | Year: 2016

In staphylococci, quorum sensing regulates both biofilm formation and toxin production, moreover it has been demonstrated to be inhibited by RNAIII inhibiting peptide (RIP). Aim our study was to evaluate the in vitro activity and its in vivo efficacy of the combined administration of FS10, a novel RIP derivative, and tigecycline in an animal model of methicillin-resistant (MR) and methicillin-sensitive (MS) Staphylococcus aureus wound infection. Using a 1.x2 cm template, one full thickness wound was established through the panniculus carnosus on the back subcutaneous tissue of each animal. Infection was determined by inoculation of 5x107 CFU/ml of bacteria, that produced an abscess within 24 h, after this, treatment was initiated. The study included, for each strain, a control group without infection, a control infected group that did not receive any treatment and a control infected group with drug-free foam dressing, and three infected groups treated, respectively, with: FS10-soaked foam dressing (containing 20 g FS10), daily intraperitoneal tigecycline (7 mg/Kg), FS10-soaked foam dressing (containing 20 g FS10) and daily intraperitoneal injections of tigecycline (7 mg/Kg). The main outcome measures were quantitative culture and histological examination of tissue repair. The highest inhibition of infection was achieved in the group that received FS10-soaked and parenteral tigecycline reducing the bacterial load from 107 CFU/ml to about 103 CFU/g for MSSA and to about 104 CFU/g for MRSA. The group treated with FS10-soaked foam dressing associated with parenteral tigecycline showed, histologically, better overall healing with epithelialization and collagen scores significantly higher than those of the other groups in both strains. In conclusion, the combined use of topical FS10 with i.p. tigecycline induced positive interaction in vivo, resulting in an enhanced therapeutic benefit versus staphylococcal infections in murine wound models.


Spreghini E.,Marche Polytechnic University | Orlando F.,Experimental Animal Models for Aging Units | Tavanti A.,University of Pisa | Senesi S.,University of Pisa | And 3 more authors.
Journal of Antimicrobial Chemotherapy | Year: 2012

Objectives: The aim of the present study was to compare, in vitro and in vivo, the effects of caspofungin, micafungin and anidulafungin against Candida parapsilosis complex isolates. Methods: In vitro activities of all three echinocandins were assessed against C. parapsilosis sensu stricto (n = 4), Candida orthopsilosis (n = 4) and Candida metapsilosis (n = 3) using broth microdilution susceptibility testing, minimum fungicidal concentration determination and a killing-curve assay, in the absence and in the presence of 50% human serum. Then, the activities of all drugs were investigated in an immunocompromised murine model of systemic candidiasis. Animals were infected with six isolates (two for each species) and treated with the echinocandins administered at 0.25, 1, 5 and 10 mg/kg/day for six consecutive days. Fungal burdens were assessed in kidney tissues on day 7 post-infection. Results: Geometric mean MICs of caspofungin, micafungin and anidulafungin for C. parapsilosis sensu lato were, respectively, 0.09, 0.14 and 0.20 mg/L without serum, and 0.70, 3.92 and 5.84 mg/L with serum. The fungicidal activity of all three echinocandins was variable; however, the addition of serum reduced the fungicidal effects against these species. In vivo studies showed that caspofungin at 5 and 10 mg/kg/day significantly decreased the kidney burdens with respect to the controls for all isolates, while micafungin was active at 5 and/or 10 mg/kg/day only against C. metapsilosis. Conclusions: Our susceptibility testing showed that caspofungin was the most active echinocandin against all three species. Also, caspofungin resulted in significant therapeutic effects for treatments of experimental systemic infections due to the three species, while micafungin was effective only against C. metapsilosis. © The Author 2012. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved.


Cirioni O.,Marche Polytechnic University | Kamysz E.,University of Gdansk | Ghiselli R.,Marche Polytechnic University | Kamysz W.,Medical University of Gdańsk | And 10 more authors.
Journal of Antimicrobial Chemotherapy | Year: 2011

Objectives: An experimental study was performed to evaluate both in vitro and in vivo the kind of interaction between the Laur-CKK-NH2 dimer and daptomycin using two Enterococcus faecalis strains with different patterns of susceptibilities. Methods: We evaluated whether selection for daptomycin-resistant E. faecalis could be prevented in vitro by combining daptomycin with the Laur-CKK-NH2 dimer. The strains were serially exposed in broth to 2-fold stepwise increasing concentrations of daptomycin alone or in combination with a fixed concentration (0.25×MIC) of the Laur-CKK-NH2 dimer. We also performed an in vitro synergy study. For in vivo studies, a mouse model of enterococcal sepsis was used. Results: In vitro experiments: exposure to daptomycin alone gradually selected for enterococci with increased MICs; and the Laur-CKK-NH2 dimer showed a positive interaction with daptomycin and was able to prevent the resistance. In vivo experiments: the main outcome measures were lethality and quantitative blood cultures; and the Laur-CKK-NH2 dimer combined with daptomycin exhibited the highest efficacy for all main outcome measurements. Conclusions: These results highlight the potential usefulness of combining daptomycin with the Laur-CKK-NH2 dimer. The combination provides a future therapeutic alternative for the treatment of enterococcal severe infections. © Crown 2011.


PubMed | Experimental Animal Models for Aging Units, Marche Polytechnic University, Medical University of Gdańsk and University of Gdansk
Type: | Journal: Peptides | Year: 2014

The aim of our study was to evaluate the in vitro activity of IB-367 and its bactericidal effect for Pseudomonas aeruginosa and Escherichia coli, associated to a synergic study to test the antibiotic combinations between the peptide and colistin or imipenem. Minimum inhibitory concentrations (MICs), the minimum bactericidal concentrations (MBCs), the synergy test and killing study were carried out to evaluate the IB-367 activity. In the in vivo model, a wound was incised through the panniculus carnosus of BALB/c mice, and then inoculated with 5 107 colony-forming units of P. aeruginosa and E. coli. For each strain, the study included an infected or not infected group that did not receive any treatment, and five contaminated groups treated with local IB- 367, intraperitoneal imipenem, intraperitoneal colistin, topical IB-367 local plus intraperitoneal imipenem or intraperitoneal colistin. All isolates were inhibited by IB-367 at concentrations of 4-64 mg/l. Killing by IB-367 was shown to be very rapid: its activity on all Gram-negative bacteria was completed within a 40 min exposure period at a concentration of 2 MIC/l. Synergy was demonstrated when IB-367 was combined with colistin or imipenem. In in vivo studies, the groups treated with topical IB-367 and intraperitoneal colistin showed the best results in terms of bacterial load inhibition either for Pseudomonas or for E. coli. The good in vitro activity and in vivo efficacy, as well as, the synergic interactions with antibiotics suggest that IB-367 is a promising candidate for potential application in the treatment of wound Gram-negative infections.


Spreghini E.,Marche Polytechnic University | Orlando F.,Experimental Animal Models for Aging Units | Sanguinetti M.,Catholic University of the Sacred Heart | Posteraro B.,Catholic University of the Sacred Heart | And 3 more authors.
Antimicrobial Agents and Chemotherapy | Year: 2012

The aim of this study was to compare the in vitro and in vivo activities of micafungin, caspofungin, and anidulafungin against Candida glabrata. The MICs against 28 clinical isolates showed that the overall susceptibilities to caspofungin and to micafungin were not statistically different in the absence of human serum, whereas the isolates were less susceptible to micafungin than to caspofungin in its presence. Minimum fungicidal concentrations, as well as time-kill experiments, showed that caspofungin was more active than anidulafungin, while micafungin was superior to either caspofungin or anidulafungin without serum; its addition rendered caspofungin and micafungin equally effective. A murine model of systemic candidiasis against a C. glabratasusceptible isolate was performed to study the effects of all three echinocandins, and kidney burden counts showed that caspofungin, micafungin, and anidulafungin were active starting from 0.25, 1, and 5 mg/kg of body weight/day, respectively. Two echinocandin-resistant strains of C. glabrata were selected: C. glabrata 30, a laboratory strain harboring the mutation Fks2p- P667T, and C. glabrata 51, a clinical isolate harboring the mutation Fks2p-D666G. Micafungin activity was shown to be as effective as or more effective than that of caspofungin or anidulafungin in terms of MICs. In vivo studies against these resistant strains showed that micafungin was active starting from 1 mg/kg/day, while caspofungin was effective only when administrated at higher doses of 5 or 10 mg/kg/day. Although a trend toward colony reduction was observed with the highest doses of anidulafungin, a significant statistical difference was never reached. Copyright © 2012, American Society for Microbiology. All Rights Reserved.


Pozzi V.,Marche Polytechnic University | Sartini D.,Marche Polytechnic University | Morganti S.,Marche Polytechnic University | Giuliante R.,Marche Polytechnic University | And 10 more authors.
PLoS ONE | Year: 2013

Oral squamous cell carcinoma (OSCC) is the most common type of oral cancer. Despite progress in the treatment of OSCC, overall survival has not improved substantially in the last three decades. Therefore, identification of reliable biomarkers becomes essential to develop effective anti-cancer therapy. In this study, we focused on the enzyme Nicotinamide N-methyltransferase (NNMT), which plays a fundamental role in the biotransformation of many xenobiotics. Although several tumors have been associated with abnormal NNMT expression, its role in cancer cell metabolism remains largely unknown. In this report, 7 human oral cancer cell lines were examined for NNMT expression by Real-Time PCR, Western blot and HPLC-based catalytic assay. Subsequently, we evaluated the in vitro effect of shRNA-mediated silencing of NNMT on cell proliferation. In vivo tumorigenicity of oral cancer cells with stable knockdown of NNMT was assayed by using xenograft models. High expression levels of NNMT were found in PE/CA PJ-15 cells, in keeping with the results of Western blot and catalytic activity assay. PE/CA PJ-15 cell line was stably transfected with shRNA plasmids against NNMT and analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and soft agar Assays. Transfected and control cells were injected into athymic mice in order to evaluate the effect of NNMT silencing on tumor growth. NNMT downregulation resulted in decreased cell proliferation and colony formation ability on soft agar. In athymic mice, NNMT silencing induced a marked reduction in tumour volume. Our results show that the downregulation of NNMT expression in human oral carcinoma cells significantly inhibits cell growth in vitro and tumorigenicity in vivo. All these experimental data seem to suggest that NNMT plays a critical role in the proliferation and tumorigenic capacity of oral cancer cells, and its inhibition could represent a potential molecular approach to the treatment of oral carcinoma. © 2013 Pozzi et al.


Spreghini E.,Marche Polytechnic University | Orlando F.,Experimental Animal Models for Aging Units | Giannini D.,Marche Polytechnic University | Barchiesi F.,Marche Polytechnic University
Journal of Antimicrobial Chemotherapy | Year: 2010

Objectives: We analysed the in vitro and in vivo effects of posaconazole and amphotericin B against three clinical isolates of zygomycetes: Lichtheimia corymbifera, F1; and Rhizopus oryzae, F5 and F6. Methods: In vitro activities of both drugs were assessed by determining MICs, minimum fungicidal concentrations (MFCs) and fungal damage measured by the XTT assay against either the spores or the hyphal forms. Additionally, the survival curves of neutropenic mice systemically infected with the zygomycete isolates were used as the marker of antifungal response to amphotericin B (1 mg/kg/day) or posaconazole (2.5, 10 and 50 mg/kg/day). Results: In terms of MICs, posaconazole proved to be active against the three isolates (MICs ranging from 0.125 to 1.0 mg/L). The median posaconazole MFCs were 0.25, 0.5 and >16 mg/L for F1, F5 and F6, respectively. The XTT assay showed that posaconazole was active against spores of all three isolates, but only partially effective against the hyphae. The survival studies showed that amphotericin B at 1 mg/kg/day and posaconazole at 10 mg/kg/day prolonged the survival of the animals infected with L. corymbifera F1. In mice infected with R. oryzae F5, only posaconazole at 50 mg/kg/day significantly prolonged survival, whereas amphotericin B at 1 mg/kg/day was the only regimen active against R. oryzae F6. Conclusions: Our findings showed that posaconazole could be useful in the treatment of zygomycosis. Also, we report that an isolate of R. oryzae with low MFC responded to posaconazole, while another isolate with high MFC did not. © The Author 2010. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved.


Cirioni O.,Marche Polytechnic University | Mocchegiani F.,Marche Polytechnic University | Ghiselli R.,Marche Polytechnic University | Silvestri C.,Marche Polytechnic University | And 6 more authors.
European Journal of Vascular and Endovascular Surgery | Year: 2010

Objective: To investigate the efficacy of daptomycin and rifampin either alone or in combination in preventing prosthesis biofilm in a rat model of staphylococcal vascular graft infection. Design: Prospective, randomised, controlled animal study. Materials: Graft infections were established in the back subcutaneous tissue of adult male Wistar rats by implantation of Dacron prostheses followed by topical inoculation with 2 × 107 colony forming units of Staphylococcus aureus, strain Smith diffuse. Methods: The study included a control group, a contaminated group that did not receive any antibiotic prophylaxis and three contaminated groups that received intra-peritoneal daptomycin, rifampin-soaked graft and daptomycin plus rifampin-soaked graft, respectively. Each group included 15 animals. The infection burden was evaluated by using sonication and quantitative agar culture. Moreover, an in vitro antibiotic susceptibility assay for S. aureus biofilms was performed to elucidate the same activity. Results: When tested alone, daptomycin and rifampin showed good efficacies. Their combination showed efficacies significantly higher than that of each single compound. The in vitro studies showed that Minimum Inhibitory Concentration and Minimum Bactericidal Concentration values for daptomycin were lower in presence of rifampin. Daptomycin prevented the emergence of rifampin resistance. Conclusion: Daptomycin is an important candidate for prevention of staphylococcal biofilm-related infection and rifampin could serve as an interesting anti-staphylococcal antibiotic enhancer.


Cirioni O.,Marche Polytechnic University | Ghiselli R.,Marche Polytechnic University | Silvestri C.,Marche Polytechnic University | Minardi D.,Marche Polytechnic University | And 7 more authors.
Journal of Antimicrobial Chemotherapy | Year: 2011

Objectives: An experimental study was performed to evaluate both in vitro and in vivo the efficacy of clarithromycin coating combined with systemic amikacin in preventing ureteral stent biofilm infection due to Pseudomonas aeruginosa. Methods: The activities of the two antibiotics were studied in vitro in the absence or in the presence of biofilm. For the in vivo study we evaluated a control group without bacterial challenge to evaluate the sterility of the surgical procedure, a challenged control group that did not receive any antibiotic prophylaxis and three challenged groups that received (i) 15 mg/kg intraperitoneal amikacin immediately after stent implantation, (ii) clarithromycin-coated ureteral stents where 0.2 cm2 sterile ureteral stents were incubated in 10 mg/L clarithromycin solution for 30 min immediately before implantation, and (iii) intraperitoneal amikacin plus a clarithromycin-coated ureteral stent at the above concentrations. Results: The in vitro studies showed that the biofilm was strongly affected by the presence of clarithromycin and, in its presence, amikacin had MICs and MBCs lower than those obtained in the absence of clarithromycin. For the singly treated groups, intraperitoneal amikacin showed the strongest effect on bacterial numbers. A clarithromycin coating combined with systemic amikacin showed an efficacy that was higher than that of each single compound. Conclusions: The prevention of ureteral stent Pseudomonas biofilm infection was enhanced by impregnation of the stent with clarithromycin combined with systemic amikacin. © The Author 2011. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved.

Loading Experimental Animal Models for Aging Units collaborators
Loading Experimental Animal Models for Aging Units collaborators