Effects of an amino acid buffered hypochlorite solution as an adjunctive to air-powder abrasion in open-flap surface decontamination of implants failed for peri-implantitis: an ex vivo randomized clinical trial.

OBJECTIVES: To evaluate ex vivo the efficacy of an amino acid buffered hypochlorite solution supplemented to surface debridement with air-powder abrasion in removing bacterial biofilm following open-flap decontamination of implants failed due to peri-implantitis. MATERIALS AND METHODS: This study was an ex vivo, single-blind, randomized, intra-subject investigation. Study population consisted of 20 subjects with at least three implants failed for peri-implantitis (in function for > 12 months and progressive bone loss exceeding 50%) to be explanted. For each patient, implants were randomly assigned to surface decontamination with sodium bicarbonate air-powder abrasion (test-group 1) or sodium bicarbonate air-powder abrasion supplemented by amino acid buffered hypochlorite solution (test-group 2) or untreated control group. Following open-flap surgery, untreated implants (control group) were explanted. Afterwards, test implants were decontaminated according to allocation and explanted. Microbiological analysis was expressed in colony-forming units (CFU/ml). RESULTS: A statistically significant difference in the concentrations of CFU/ml was found between implants of test-group 1 (63,018.18 ± 228,599.36) (p = 0.007) and implants of test-group 2 (260.00 ± 375.80) (p < 0.001) compared to untreated implants (control group) (86,846.15 ± 266,689.44). The concentration of CFU/ml on implant surfaces was lower in test-group 2 than in test-group 1, with a statistically significant difference (p < 0.001). CONCLUSION: The additional application of amino acid buffered hypochlorite solution seemed to improve the effectiveness of implant surface decontamination with air-powder abrasion following open-flap surgery. CLINICAL RELEVANCE: Lacking evidence on the most effective method for biofilm removal from contaminated implant surfaces, the present experimental study provides further information for clinicians and researchers.

Primary retroperitoneal abscesses due to Rhodococcus equi in a patient with severe nephrotic syndrome: successful antibiotic treatment with linezolid and tigecycline.

We present a case of Rhodococcus equi primary retroperitoneal abscesses without pulmonary involvement in an immunocompromised patient with severe nephrotic syndrome. No risk factors for exposure to R. equi were present. The infection was successfully treated with long-term combination antibiotic treatment including linezolid and tigecycline.

Effect of limonin and nomilin on HIV-1 replication on infected human mononuclear cells.

In the last years several plant-derived natural compounds have been screened for their anti-HIV activity in order to find lead compounds with novel structures or mechanisms of action. Among these, several triterpenoids have been found to exhibit an antiretroviral activity with different mechanisms of action. In this study the effect of two limonoids, limonin and nomilin, on the growth of human immunodeficiency virus-1 (HIV-1) in culture of human peripheral blood mononuclear cells (PBMC) and on monocytes/macrophages (M/M) is described. Limonin and nomilin were found to inhibit the HIV-1 replication in all cellular systems used. A dose-dependent inhibition of viral replication was observed in PBMC isolated from healthy donors and infected with HIV-1 strain after incubation with limonin and nomilin (EC (50) values: 60.0 microM and 52.2 microM, respectively). The two terpenoids inhibited at all concentrations studied the production of HIV-p24 antigen even when the PBMC employed were chronically infected (EC (50) values of 61.0 microM for limonin and 76.2 microM for nomilin). Moreover, these compounds inhibited the HIV-1 replication even in infected M/M. In this cellular system the inhibitory effect was significant at the concentrations of 20 microM, 40 microM and 80 microM starting from day 14 and reached the maximum effect after 18 days of incubation. As regards the mechanism of action, limonin and nomilin inhibit in vitro HIV-1 protease activity. In general, the results obtained point out a similar anti-HIV activity of limonin and nomilin indicating that this activity is not drastically influenced by the structural difference between the two compounds.

In vitro anti-HIV activity of oleanolic acid on infected human mononuclear cells.

Oleanolic acid is a triterpenoid which is quite common in nature in the form either of free acid or in triterpenoid saponin glycosides. This study describes the effect of oleanolic acid on the growth of human immunodeficiency virus-1 (HIV-1) in cultures of human peripheral mononuclear cells (PBMC) and of monocyte/macrophages (M/M). Its inhibitory activity was also evaluated on PBMC obtained from HIV-1 infected patients. Results obtained show that oleanolic acid inhibits the HIV-1 replication in all the cellular systems used (EC50 values: 22.7 microM, 24.6 microM and 57.4 microM for in vitro infected PBMC, naturally infected PBMC and M/M, respectively). As regards the mechanism of action, oleanolic acid inhibits in vitro the HIV-1 protease activity.