In vitro antifungal activity of Morinda citrifolia (noni) extract against Candida albicans.

INTRODUCTION: Candida albicans is the main agent of the most common fungal infection, Candidiasis. It is an opportunistic and dangerous pathogen, especially in immunosuppressed patients. The biological properties of Morinda citrifolia (noni) make it a potent antifungal. In this study, antifungal effect of M. citrifolia was evaluated to verify its effect on human cells. METHODOLOGY: Extract of M. citrifolia was used against strains of C. albicans (cEC 1291). Glucose consumption in C. albicans biofilm was determined at different concentrations of M. citrifolia, and germ tube formation was evaluated in the presence and absence of M. citrifolia. Fungicidal activity was determined by the kinetics of fungal cell death. THP-1 and HeLa cells were used for cell viability and apoptosis, and cell proliferation assays, respectively. RESULTS: Cells treated with M. citrifolia maintained higher concentration of glucose than the control group (p < 0.05). Germ tube formation was inhibited in cells treated with M. citrifolia (p < 0.05). M. citrifolia exerted a cytotoxic effect on C. albicans cells with 99.99% lethality after 6.82 h (1:1 and 1:2), and reduced the viability of THP-1 cells by 25% and 67% after 12 and 36 h, respectively. Annexin V expression in THP-1 increased in groups that received higher concentrations of M. citrifolia (p < 0.05), reducing the proliferation of THP-1 and HeLa cells (2.8-fold). A greater cytotoxic effect was observed in fungal cells. CONCLUSIONS: These results indicate that M. citrifolia exerts biological activity against C. albicans and reduces the viability and proliferation of human cells.

Analysis of Macrophage Activation Markers in an Experimental Model of Cutaneous Leishmaniasis Treated with Photodynamic Therapy Mediated by 5-Aminolevulinic Acid.

Objective: In this study, we evaluated the effectiveness of photodynamic therapy (PDT) for the treatment of experimental cutaneous leishmaniasis (CL) and the profile of macrophages activation markers. Background: Leishmaniasis is an infectious disease caused by parasites of the genus Leishmania. CL is caused by Leishmania major in the old world and by Leishmania braziliensis in the Americas. Considering the targeted organs, PDT may constitute a valuable therapeutic intervention. Macrophages are the host cells of Leishmania in mammals and may be classified into type M1 or M2 depending on the pattern of activation. Methods: BALB/c mice were infected in the foot pad with 1 × 106 amastigotes of L. braziliensis and treated with 5-aminolevulinic acid (5-ALA), visible light, or 5-ALA-PDT. The ex vivo mRNA expression levels of interleukin-10, tumor necrosis factor-α (TNF-α), arginase-1, heme oxygenase ( Hmox), and induced nitric oxide synthase (iNOS) were quantities as markers of macrophage activation with distinct ability to kill intracellular parasite. Results: The parasite load decreased significantly in the group treated with PDT compared with the other groups. The iNOS relative mRNA was higher in the group treated with PDT and light only compared with the group without treatment, whereas iNOS/arginase ratio was significantly higher only in the PDT group. The expression of TNF-α was significantly higher in 5-ALA and light compared with PDT and control group. No significant difference was observed in the expression of the other markers evaluated. Conclusions: Both, light and 5-ALA-PDT were able to upregulate iNOS expression only; 5-ALA-PDT was able to reduce parasite burden. The increase in the iNOS levels suggests it might participate in the antimicrobial mechanisms triggered by 5-ALA-PDT; although parasite death mechanism was not completely clarified, the results presented in this study suggest that macrophage activation may contribute to parasite control.

Antibiotic Resistance of Bacteria Involved in Urinary Infections in Brazil: A Cross-Sectional and Retrospective Study.

Empirical and prolonged antimicrobial treatment of urinary tract infections caused by Escherichia coli is associated with the emergence of bacterial resistance, and not all countries have strict policies against the indiscriminate use of drugs in order to prevent resistance. This cross-sectional and retrospective study (2010-2015) aimed to evaluate the sensitivity and resistance of patient-derived E. coli to different drugs broadly used to treat urinary infections in Brazil: ampicillin + sulbactam, cephalothin, ciprofloxacin, norfloxacin, and nitrofurantoin. We obtained 1654 E. coli samples from ambulatory patients with disease symptoms of the urinary tract from a Brazilian public hospital. While all antibiotics were effective in killing E. coli to a large degree, nitrofurantoin was the most effective, with fewer samples exhibiting antibiotic resistance. We assessed the costs of generic and brand name versions of each antibiotic. Nitrofurantoin, the most effective antibiotic, was the cheapest, followed by the fluoroquinolones (ciprofloxacin and norfloxacin), ampicillin + sulbactam and, lastly, cephalothin. Finally, assessment of antibiotic resistance to fluoroquinolones over the study period and extrapolation of the data led to the conclusion that these antibiotics could no longer be effective against E. coli-based urinary infections in approximately 20 years if their indiscriminate use in empirical treatment continues.

TGF-ß1 and BMP-4 carried by liposomes enhance the healing process in alveolar bone.

OBJECTIVE: In this work we evaluated the bone-forming potential of BMP4, TGFß1 and BMP4/TGFß1 mixed by performing histological and morphometric analysis. We also evaluated the immunolabelling of fibronectin (FN) and collagen type III (Col III), two determinant proteins for the early phase of bone repair. DESIGN: Histological, histomorphometric and immunohistochemistry analysis were used to evaluate new bone and blood vessels formation as well as fibronectin and collagen type III expression. 112 male Wistar rats weighing 250-300g had their maxillary second molar extracted. Sockets filled with blood clot (BC) or treated with L (empty liposome), P (PBS), BP (BMP-4 in PBS) and TP (TGF-ß1 in PBS), as well as with BL (BMP-4 in liposome) and TL (TGF-ß1 in liposome) administered isolated or in association (BTL) were obtained. The animals were sacrificed at 3, 7, 14 and 21 days after surgery. RESULTS: An increased percentage of bone trabeculae, and a higher number of blood vessels were observed in groups BL or TL administered isolated or in association when compared to groups BC, L, P, BP and TP. Fibronectin and collagen type III analysis revealed enhanced expression firstly detected at 3 days followed by a peak at 7 days. Lower levels of immunoreactivity were observed in the sockets filled with blood clot, and treated with L, P, BP and TP when compared with sockets from groups BL, TL and BTL. CONCLUSION: The present study indicates growth factors carried by liposomes, either in isolated or associated forms, as successful enhancers of the healing process in rat tooth sockets. We also conclude that the expression of fibronectin and collagen type III increases during the early phases of bone repair.

Analysis of the properties of dental cements after exposure to incubation media containing Streptococcus mutans.

AIM: Indirect restorations are increasingly used in dentistry, and the cementation interface is possibly the most critical region of the work. The objective of the present work was to evaluate the influence of exposure to a culture medium containing S. mutans on the hardness and solubility of four different cementing agents (zinc phosphate, glass ionomer, glass ionomer modified with resin and resin cement). MATERIALS AND METHODS: Test specimens composed of these cements were exposed for 30 days in a culture medium containing S. mutans. After leaching, the test materials were assessed in terms of their solubility (loss of mass) and Knoop (KHN) microhardness. Changes in surface morphology were identified using scanning electron microscopy (SEM). RESULTS: The resin cement showed no significant solubility and its hardness increased following exposure and leaching, while the zinc phosphate cement was the most soluble and its hardness decreased after exposure to the culture medium. SEM analyses identified morphological alterations on the surfaces of the test materials that were compatible with the solubility results. CONCLUSION: It is concluded that resinous cements perform better than water-based cements when exposed to acidic conditions. CLINICAL SIGNIFICANCE: The effects of acids from Streptococcus mutans can interfere with the efficiency and properties of some cements used for fixation of indirect restorations, exposed to the buccal environment.

Photodynamic therapy with rose bengal induces GroEL expression in Streptococcus mutans.

UNLABELLED: Heat-shock proteins (HSPs) are indicative of stressing conditions that may affect cell viability. In Streptococcus mutans, acid stress induces high levels of GroEL, an HSP, in addition to metabolic alterations, as shown by proteomic analysis. OBJECTIVE: We tested whether the expression of GroEL by S. mutans was enhanced after photodynamic therapy (PDT) with rose bengal. METHODS: S. mutans was grown in complete medium supplemented with 50 mmol/L glucose. The test conditions used were as follows: Rose bengal (0.1 micromol/L) with and without light treatment (500 mJ/cm(2)), light treatment alone, and 1 mol/L NaCl (as a stress condition). The extracellular pH of bacteria was monitored; HSP expression was assayed with Western blot, and possible DNA damage analyzed. RESULTS: Higher HSP expression was detected in bacteria after PDT treatment as compared with light or dye alone (negative controls). The expression of HSP after PDT was similar to that induced by osmotic stress. No DNA degradation was observed after PDT of S. mutans. CONCLUSIONS: PDT may cause effects similar to those of other stressing conditions in S. mutans, and cell death induced by this treatment reflects its incapacity to protect itself sufficiently against the deleterious effects of PDT with Rose bengal.

Photodynamic therapy in planktonic and biofilm cultures of Aggregatibacter actinomycetemcomitans.

OBJECTIVE: To evaluate the inactivation of Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), responsible for causing aggressive periodontitis, using photodynamic therapy (PDT) by rose bengal (RB) as a model of a reactive oxygen species (ROS) generator, in planktonic and biofilm cultures. MATERIALS AND METHODS: A. actinomycetemcomitans was grown in planktonic and biofilm cultures using tryptic soy broth medium. The sensibility (dark toxicity) to RB was determined, and its ideal concentration for PDT was established. Concentrations in the range from 0.01 to 50.0 micromol L(-1) RB, with different light potencies and incubation times, were used. An odontological resin photopolymerizer that emits the adequate wavelength for absorption of the RB dye was applied. Bacterial viability was determined by colony- forming units (CFU). RESULTS: RB photosensitizer dye in concentrations up to 0.1 micromol L(-1) did not show toxicity per se toward A. actinomycetemcomitans cells. In a PDT study with photoirradiation (1 min) at 0.1 micromol L(-1), a 55% reduction of A. actinomycetemcomitans viability was obtained in planktonic cultures. Preincubation (30 min) of the bacteria with the dye resulted in a 90% reduction of its viability. It is important to note that, for dye concentrations up to 1 micromol L(-1), in the same experimental conditions, no death effect on gingival fibroblasts was observed. The A. actinomycetemcomitans biofilm was not affected by RB or light alone. After PDT, the reduction in the biofilm (about 45%) is significantly dependant on RB concentration and irradiation time when this dye was used as a ROS generator. CONCLUSION: Photodynamic therapy-generated ROS inactivates A. actinomycetemcomitans both in planktonic and biofilm cultures, even in small concentrations of the photosensitizing agent, and it does not cause damage to fibroblast cells under the same conditions.